[Cleanup] Remove StringPrintf from global namespace

use of StringPrintf now requires prefixing with base:: or a per-scope using directive TBR'd: abodenha: chrome/service brettw: content, third_party, webkit darin: base, chrome/browser, chrome/renderer dgarret: courgette enne: cc fischmann: media gbillock: sql joi: google_apis,components rsleevi: net, crypto sky: chrome/test thestig: printing, chrome/common, tsepez: ipc wez: remoting yfriedman: testing/android NOTRY=true R=brettw@chromium.org TBR=joi@chromium.org, rsleevi@chromium.org, enne@chromium.org, thestig@chromium.org, darin@chromium.org, abodenha@chromium.org, sky@chromium.org, dgarret@chromium.org, tsepez@chromium.org, fishman@chromium.org, wez@chromium.org, gbillock@chromium.org, yfriedman@chromium.org BUG= Review URL: https://codereview.chromium.org/12767006 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@188857 0039d316-1c4b-4281-b951-d872f2087c98
author: groby@chromium.org <groby@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> 2013-03-18 22:33:04 +0000
committer: groby@chromium.org <groby@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> 2013-03-18 22:33:04 +0000
commit: 7d3cbc90c089bb3ba5cb81a5abdc0846d5826def (patch)
tree: 8ad0db2d4581c8e935ed1b07c6b4147a5350a204
parent: bb192b87059a76b89fbc20ad08347c28656e838d (diff)
download: chromium_src-7d3cbc90c089bb3ba5cb81a5abdc0846d5826def.zip
chromium_src-7d3cbc90c089bb3ba5cb81a5abdc0846d5826def.tar.gz
chromium_src-7d3cbc90c089bb3ba5cb81a5abdc0846d5826def.tar.bz2
191 files changed, 757 insertions, 695 deletions
diff --git a/android_webview/browser/aw_devtools_delegate.cc b/android_webview/browser/aw_devtools_delegate.cc
index cfac7f7..889352d 100644
--- a/android_webview/browser/aw_devtools_delegate.cc
+++ b/android_webview/browser/aw_devtools_delegate.cc
@@ -26,7 +26,7 @@ AwDevToolsDelegate::AwDevToolsDelegate(content::BrowserContext* browser_context)
     : browser_context_(browser_context) {
   devtools_http_handler_ = content::DevToolsHttpHandler::Start(
       new net::UnixDomainSocketWithAbstractNamespaceFactory(
-          StringPrintf(kSocketNameFormat, getpid()),
+          base::StringPrintf(kSocketNameFormat, getpid()),
           base::Bind(&content::CanUserConnectToDevTools)),
       "",
       this);
diff --git a/ash/display/display_controller.cc b/ash/display/display_controller.cc
index 47cd665..2db32f7 100644
--- a/ash/display/display_controller.cc
+++ b/ash/display/display_controller.cc
@@ -249,7 +249,7 @@ bool DisplayLayout::ConvertToValue(const DisplayLayout& layout,
 
 std::string DisplayLayout::ToString() const {
   const std::string position_str = GetStringFromPosition(position);
-  return StringPrintf("%s, %d", position_str.c_str(), offset);
+  return base::StringPrintf("%s, %d", position_str.c_str(), offset);
 }
 
 // static
@@ -768,7 +768,8 @@ aura::RootWindow* DisplayController::CreateRootWindowForDisplay(
   params.initial_insets = display_info.GetOverscanInsetsInPixel();
   params.initial_root_window_scale = display_info.ui_scale();
   aura::RootWindow* root_window = new aura::RootWindow(params);
-  root_window->SetName(StringPrintf("RootWindow-%d", root_window_count++));
+  root_window->SetName(
+      base::StringPrintf("RootWindow-%d", root_window_count++));
 
   // No need to remove RootWindowObserver because
   // the DisplayManager object outlives RootWindow objects.
diff --git a/ash/display/display_manager.cc b/ash/display/display_manager.cc
index 257e62b..ad92a5e 100644
--- a/ash/display/display_manager.cc
+++ b/ash/display/display_manager.cc
@@ -526,7 +526,8 @@ void DisplayManager::CycleDisplayImpl() {
     gfx::Rect host_bounds =
         gfx::Rect(primary->GetHostOrigin(),  primary->GetHostSize());
     new_display_info_list.push_back(DisplayInfo::CreateFromSpec(
-        StringPrintf("%d+%d-500x400", host_bounds.x(), host_bounds.bottom())));
+        base::StringPrintf(
+            "%d+%d-500x400", host_bounds.x(), host_bounds.bottom())));
   }
   UpdateDisplays(new_display_info_list);
 }
diff --git a/ash/display/display_manager_unittest.cc b/ash/display/display_manager_unittest.cc
index 2b53645..e4305fa 100644
--- a/ash/display/display_manager_unittest.cc
+++ b/ash/display/display_manager_unittest.cc
@@ -23,6 +23,8 @@ namespace internal {
 using std::vector;
 using std::string;
 
+using base::StringPrintf;
+
 class DisplayManagerTest : public test::AshTestBase,
                            public gfx::DisplayObserver,
                            public aura::WindowObserver {
diff --git a/ash/magnifier/magnification_controller_unittest.cc b/ash/magnifier/magnification_controller_unittest.cc
index bc2c5ad..2060df4 100644
--- a/ash/magnifier/magnification_controller_unittest.cc
+++ b/ash/magnifier/magnification_controller_unittest.cc
@@ -28,7 +28,7 @@ class MagnificationControllerTest: public test::AshTestBase {
 
   virtual void SetUp() OVERRIDE {
     AshTestBase::SetUp();
-    UpdateDisplay(StringPrintf("%dx%d", kRootWidth, kRootHeight));
+    UpdateDisplay(base::StringPrintf("%dx%d", kRootWidth, kRootHeight));
 
     aura::RootWindow* root = GetRootWindow();
     gfx::Rect root_bounds(root->bounds());
diff --git a/ash/system/monitor/tray_monitor.cc b/ash/system/monitor/tray_monitor.cc
index b6f134a..e34ffb5 100644
--- a/ash/system/monitor/tray_monitor.cc
+++ b/ash/system/monitor/tray_monitor.cc
@@ -65,12 +65,12 @@ void TrayMonitor::OnGotHandles(const std::list<base::ProcessHandle>& handles) {
   std::string output;
   string16 free_bytes =
       ui::FormatBytes(static_cast<int64>(mem_info.free) * 1024);
-  output = StringPrintf("free: %s", UTF16ToUTF8(free_bytes).c_str());
+  output = base::StringPrintf("free: %s", UTF16ToUTF8(free_bytes).c_str());
   if (mem_info.gem_size != -1) {
     string16 gem_size = ui::FormatBytes(mem_info.gem_size);
-    output += StringPrintf("  gmem: %s", UTF16ToUTF8(gem_size).c_str());
+    output += base::StringPrintf("  gmem: %s", UTF16ToUTF8(gem_size).c_str());
     if (mem_info.gem_objects != -1)
-      output += StringPrintf("  gobjects: %d", mem_info.gem_objects);
+      output += base::StringPrintf("  gobjects: %d", mem_info.gem_objects);
   }
   size_t total_private_bytes = 0, total_shared_bytes = 0;
   for (std::list<base::ProcessHandle>::const_iterator i = handles.begin();
@@ -85,9 +85,9 @@ void TrayMonitor::OnGotHandles(const std::list<base::ProcessHandle>& handles) {
   string16 private_size = ui::FormatBytes(total_private_bytes);
   string16 shared_size = ui::FormatBytes(total_shared_bytes);
 
-  output += StringPrintf("\nGPU private: %s  shared: %s",
-                         UTF16ToUTF8(private_size).c_str(),
-                         UTF16ToUTF8(shared_size).c_str());
+  output += base::StringPrintf("\nGPU private: %s  shared: %s",
+                               UTF16ToUTF8(private_size).c_str(),
+                               UTF16ToUTF8(shared_size).c_str());
   label_->SetText(UTF8ToUTF16(output));
   refresh_timer_.Start(FROM_HERE,
       base::TimeDelta::FromMilliseconds(kRefreshTimeoutMs),
diff --git a/ash/system/web_notification/web_notification_tray_unittest.cc b/ash/system/web_notification/web_notification_tray_unittest.cc
index a53f970..d5aba2d 100644
--- a/ash/system/web_notification/web_notification_tray_unittest.cc
+++ b/ash/system/web_notification/web_notification_tray_unittest.cc
@@ -196,7 +196,7 @@ TEST_F(WebNotificationTrayTest, ManyMessageCenterNotifications) {
   size_t notifications_to_add =
       NotificationList::kMaxVisibleMessageCenterNotifications + 1;
   for (size_t i = 0; i < notifications_to_add; ++i) {
-    std::string id = StringPrintf("test_id%d", static_cast<int>(i));
+    std::string id = base::StringPrintf("test_id%d", static_cast<int>(i));
     delegate->AddNotification(tray, id);
   }
   bool shown = tray->message_center_tray_->ShowMessageCenterBubble();
@@ -217,7 +217,7 @@ TEST_F(WebNotificationTrayTest, ManyPopupNotifications) {
   size_t notifications_to_add =
       NotificationList::kMaxVisiblePopupNotifications + 1;
   for (size_t i = 0; i < notifications_to_add; ++i) {
-    std::string id = StringPrintf("test_id%d", static_cast<int>(i));
+    std::string id = base::StringPrintf("test_id%d", static_cast<int>(i));
     delegate->AddNotification(tray, id);
   }
   // Hide and reshow the bubble so that it is updated immediately, not delayed.
diff --git a/ash/wm/drag_window_resizer_unittest.cc b/ash/wm/drag_window_resizer_unittest.cc
index 29e166a..49fe58e 100644
--- a/ash/wm/drag_window_resizer_unittest.cc
+++ b/ash/wm/drag_window_resizer_unittest.cc
@@ -37,7 +37,7 @@ class DragWindowResizerTest : public test::AshTestBase {
 
   virtual void SetUp() OVERRIDE {
     AshTestBase::SetUp();
-    UpdateDisplay(StringPrintf("800x%d", kRootHeight));
+    UpdateDisplay(base::StringPrintf("800x%d", kRootHeight));
 
     aura::RootWindow* root = Shell::GetPrimaryRootWindow();
     gfx::Rect root_bounds(root->bounds());
diff --git a/ash/wm/workspace/workspace_window_resizer_unittest.cc b/ash/wm/workspace/workspace_window_resizer_unittest.cc
index 8ffa088..a1d27e3 100644
--- a/ash/wm/workspace/workspace_window_resizer_unittest.cc
+++ b/ash/wm/workspace/workspace_window_resizer_unittest.cc
@@ -70,7 +70,7 @@ class WorkspaceWindowResizerTest : public test::AshTestBase {
 
   virtual void SetUp() OVERRIDE {
     AshTestBase::SetUp();
-    UpdateDisplay(StringPrintf("800x%d", kRootHeight));
+    UpdateDisplay(base::StringPrintf("800x%d", kRootHeight));
 
     aura::RootWindow* root = Shell::GetPrimaryRootWindow();
     gfx::Rect root_bounds(root->bounds());
diff --git a/base/debug/trace_event_android.cc b/base/debug/trace_event_android.cc
index c04ed91..70e377b 100644
--- a/base/debug/trace_event_android.cc
+++ b/base/debug/trace_event_android.cc
@@ -25,7 +25,7 @@ void WriteEvent(char phase,
                 const unsigned char* arg_types,
                 const unsigned long long* arg_values,
                 unsigned char flags) {
-  std::string out = StringPrintf("%c|%d|%s", phase, getpid(), name);
+  std::string out = base::StringPrintf("%c|%d|%s", phase, getpid(), name);
   if (flags & TRACE_EVENT_FLAG_HAS_ID)
     base::StringAppendF(&out, "-%" PRIx64, static_cast<uint64>(id));
   out += '|';
@@ -109,7 +109,7 @@ void TraceLog::SendToATrace(char phase,
     case TRACE_EVENT_PHASE_COUNTER:
       for (int i = 0; i < num_args; ++i) {
         DCHECK(arg_types[i] == TRACE_VALUE_TYPE_INT);
-        std::string out = StringPrintf("C|%d|%s-%s",
+        std::string out = base::StringPrintf("C|%d|%s-%s",
                                        getpid(), name, arg_names[i]);
         if (flags & TRACE_EVENT_FLAG_HAS_ID)
           StringAppendF(&out, "-%" PRIx64, static_cast<uint64>(id));
diff --git a/base/file_util.cc b/base/file_util.cc
index f951e3b..5567f74 100644
--- a/base/file_util.cc
+++ b/base/file_util.cc
@@ -278,7 +278,8 @@ int GetUniquePathNumber(
 
   FilePath new_path;
   for (int count = 1; count <= kMaxUniqueFiles; ++count) {
-    new_path = path.InsertBeforeExtensionASCII(StringPrintf(" (%d)", count));
+    new_path =
+        path.InsertBeforeExtensionASCII(base::StringPrintf(" (%d)", count));
     if (!PathExists(new_path) &&
         (!have_suffix || !PathExists(FilePath(new_path.value() + suffix)))) {
       return count;
diff --git a/base/file_util_posix.cc b/base/file_util_posix.cc
index 8b01412..c7014b6 100644
--- a/base/file_util_posix.cc
+++ b/base/file_util_posix.cc
@@ -140,7 +140,7 @@ bool VerifySpecificPathControlledByUser(const FilePath& path,
 
 static std::string TempFileName() {
 #if defined(OS_MACOSX)
-  return StringPrintf(".%s.XXXXXX", base::mac::BaseBundleID());
+  return base::StringPrintf(".%s.XXXXXX", base::mac::BaseBundleID());
 #endif
 
 #if defined(GOOGLE_CHROME_BUILD)
diff --git a/base/os_compat_android.cc b/base/os_compat_android.cc
index d434c5b..118ad5e 100644
--- a/base/os_compat_android.cc
+++ b/base/os_compat_android.cc
@@ -18,7 +18,7 @@
 extern "C" {
 
 int futimes(int fd, const struct timeval tv[2]) {
-  const std::string fd_path = StringPrintf("/proc/self/fd/%d", fd);
+  const std::string fd_path = base::StringPrintf("/proc/self/fd/%d", fd);
   return utimes(fd_path.c_str(), tv);
 }
 
diff --git a/base/process_linux.cc b/base/process_linux.cc
index 83d9649..b7764fc 100644
--- a/base/process_linux.cc
+++ b/base/process_linux.cc
@@ -42,8 +42,10 @@ struct CGroups {
   base::FilePath background_file;
 
   CGroups() {
-    foreground_file = base::FilePath(StringPrintf(kControlPath, kForeground));
-    background_file = base::FilePath(StringPrintf(kControlPath, kBackground));
+    foreground_file =
+        base::FilePath(base::StringPrintf(kControlPath, kForeground));
+    background_file =
+        base::FilePath(base::StringPrintf(kControlPath, kBackground));
     file_util::FileSystemType foreground_type;
     file_util::FileSystemType background_type;
     enabled =
diff --git a/base/stringprintf.h b/base/stringprintf.h
index 9a99237..3946f3d 100644
--- a/base/stringprintf.h
+++ b/base/stringprintf.h
@@ -59,10 +59,4 @@ BASE_EXPORT void StringAppendV(std::wstring* dst,
 
 }  // namespace base
 
-// Don't require the namespace for legacy code. New code should use "base::" or
-// have its own using decl.
-//
-// TODO(brettw) remove these when calling code is converted.
-using base::StringPrintf;
-
 #endif  // BASE_STRINGPRINTF_H_
diff --git a/cc/base/worker_pool.cc b/cc/base/worker_pool.cc
index cc828a8..caa3159 100644
--- a/cc/base/worker_pool.cc
+++ b/cc/base/worker_pool.cc
@@ -183,7 +183,7 @@ WorkerPool::Inner::Inner(WorkerPool* worker_pool,
         new base::DelegateSimpleThread(
           this,
           thread_name_prefix +
-          StringPrintf("Worker%lu", workers_.size() + 1).c_str()));
+          base::StringPrintf("Worker%lu", workers_.size() + 1).c_str()));
     worker->Start();
     workers_.push_back(worker.Pass());
   }
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index d3079d2..990c32b 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1909,7 +1909,7 @@ scoped_ptr<base::Value> LayerTreeHostImpl::AsValue() const {
 
 scoped_ptr<base::Value> LayerTreeHostImpl::ActivationStateAsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
-  state->SetString("lthi_id", StringPrintf("%p", this));
+  state->SetString("lthi_id", base::StringPrintf("%p", this));
   state->SetBoolean("visible_resources_ready",
                     pending_tree_->AreVisibleResourcesReady());
   state->Set("tile_manager", tile_manager_->BasicStateAsValue().release());
@@ -1918,7 +1918,7 @@ scoped_ptr<base::Value> LayerTreeHostImpl::ActivationStateAsValue() const {
 
 scoped_ptr<base::Value> LayerTreeHostImpl::FrameStateAsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
-  state->SetString("lthi_id", StringPrintf("%p", this));
+  state->SetString("lthi_id", base::StringPrintf("%p", this));
   state->Set("device_viewport_size",
              MathUtil::AsValue(device_viewport_size_).release());
   if (tile_manager_)
diff --git a/chrome/browser/android/dev_tools_server.cc b/chrome/browser/android/dev_tools_server.cc
index 8af3124..f56abc6 100644
--- a/chrome/browser/android/dev_tools_server.cc
+++ b/chrome/browser/android/dev_tools_server.cc
@@ -129,7 +129,8 @@ void DevToolsServer::Start() {
           socket_name_,
           base::Bind(&content::CanUserConnectToDevTools)),
       use_bundled_frontend_resources_ ?
-          "" : StringPrintf(kFrontEndURL, version_info.Version().c_str()),
+          "" :
+          base::StringPrintf(kFrontEndURL, version_info.Version().c_str()),
       new DevToolsServerDelegate(use_bundled_frontend_resources_));
 }
 
diff --git a/chrome/browser/autocomplete/autocomplete_match.cc b/chrome/browser/autocomplete/autocomplete_match.cc
index eeec15d..77041f2 100644
--- a/chrome/browser/autocomplete/autocomplete_match.cc
+++ b/chrome/browser/autocomplete/autocomplete_match.cc
@@ -450,7 +450,7 @@ void AutocompleteMatch::RecordAdditionalInfo(const std::string& property,
 
 void AutocompleteMatch::RecordAdditionalInfo(const std::string& property,
                                              int value) {
-  RecordAdditionalInfo(property, StringPrintf("%d", value));
+  RecordAdditionalInfo(property, base::StringPrintf("%d", value));
 }
 
 void AutocompleteMatch::RecordAdditionalInfo(const std::string& property,
diff --git a/chrome/browser/automation/automation_provider_observers.cc b/chrome/browser/automation/automation_provider_observers.cc
index 0a9c83aa..1906110 100644
--- a/chrome/browser/automation/automation_provider_observers.cc
+++ b/chrome/browser/automation/automation_provider_observers.cc
@@ -357,8 +357,8 @@ void NavigationNotificationObserver::ConditionMet(
             &dict);
       } else {
         AutomationJSONReply(automation_, reply_message_.release()).SendError(
-            StringPrintf("Navigation failed with error code=%d.",
-                         navigation_result));
+            base::StringPrintf("Navigation failed with error code=%d.",
+                               navigation_result));
       }
     } else {
       IPC::ParamTraits<int>::Write(
diff --git a/chrome/browser/automation/testing_automation_provider.cc b/chrome/browser/automation/testing_automation_provider.cc
index 9261d38..65b3d60 100644
--- a/chrome/browser/automation/testing_automation_provider.cc
+++ b/chrome/browser/automation/testing_automation_provider.cc
@@ -210,7 +210,7 @@ void DidEnablePlugin(base::WeakPtr<AutomationProvider> automation,
   } else {
     if (automation) {
       AutomationJSONReply(automation.get(), reply_message).SendError(
-          StringPrintf(error_msg.c_str(), path.c_str()));
+          base::StringPrintf(error_msg.c_str(), path.c_str()));
     }
   }
 }
@@ -1160,7 +1160,7 @@ void TestingAutomationProvider::OpenProfileWindow(
   Profile* profile = profile_manager->GetProfileByPath(base::FilePath(path));
   if (!profile) {
     AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Invalid profile path: %s", path.c_str()));
+        base::StringPrintf("Invalid profile path: %s", path.c_str()));
     return;
   }
   int num_loads;
@@ -1991,8 +1991,8 @@ void TestingAutomationProvider::SendJSONRequestWithBrowserIndex(
     IPC::Message* reply_message) {
   Browser* browser = index < 0 ? NULL : automation_util::GetBrowserAt(index);
   if (!browser && index >= 0) {
-    AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Browser window with index=%d does not exist.", index));
+    AutomationJSONReply(this, reply_message).SendError(base::StringPrintf(
+        "Browser window with index=%d does not exist.", index));
   } else {
     SendJSONRequest(browser, json_request, reply_message);
   }
@@ -2022,8 +2022,8 @@ void TestingAutomationProvider::SendJSONRequest(Browser* browser,
     (this->*handler_map_[command])(dict_value.get(), reply_message);
   // Command has no handler.
   } else {
-    error_string = StringPrintf("Unknown command '%s'. Options: ",
-                                command.c_str());
+    error_string = base::StringPrintf("Unknown command '%s'. Options: ",
+                                      command.c_str());
     for (std::map<std::string, JsonHandler>::const_iterator it =
          handler_map_.begin(); it != handler_map_.end(); ++it) {
       error_string += it->first + ", ";
@@ -2151,7 +2151,7 @@ void TestingAutomationProvider::PerformActionOnInfobar(
   WebContents* web_contents =
       browser->tab_strip_model()->GetWebContentsAt(tab_index);
   if (!web_contents) {
-    reply.SendError(StringPrintf("No such tab at index %d", tab_index));
+    reply.SendError(base::StringPrintf("No such tab at index %d", tab_index));
     return;
   }
   InfoBarService* infobar_service =
@@ -2160,8 +2160,8 @@ void TestingAutomationProvider::PerformActionOnInfobar(
   InfoBarDelegate* infobar = NULL;
   size_t infobar_index = static_cast<size_t>(infobar_index_int);
   if (infobar_index >= infobar_service->GetInfoBarCount()) {
-    reply.SendError(StringPrintf("No such infobar at index %" PRIuS,
-                                 infobar_index));
+    reply.SendError(base::StringPrintf("No such infobar at index %" PRIuS,
+                                       infobar_index));
     return;
   }
   infobar = infobar_service->GetInfoBarDelegateAt(infobar_index);
@@ -2560,7 +2560,8 @@ void TestingAutomationProvider::WaitForAllDownloadsToComplete(
 
   if (!args->GetList("pre_download_ids", &pre_download_ids)) {
     AutomationJSONReply(this, reply_message)
-        .SendError(StringPrintf("List of IDs of previous downloads required."));
+        .SendError(
+            base::StringPrintf("List of IDs of previous downloads required."));
     return;
   }
 
@@ -2605,7 +2606,7 @@ void TestingAutomationProvider::PerformActionOnDownload(
   DownloadItem* selected_item = download_manager->GetDownload(id);
   if (!selected_item) {
     AutomationJSONReply(this, reply_message)
-        .SendError(StringPrintf("No download with an id of %d\n", id));
+        .SendError(base::StringPrintf("No download with an id of %d\n", id));
     return;
   }
 
@@ -2680,7 +2681,8 @@ void TestingAutomationProvider::PerformActionOnDownload(
     selected_item->Cancel(true);
   } else {
     AutomationJSONReply(this, reply_message)
-        .SendError(StringPrintf("Invalid action '%s' given.", action.c_str()));
+        .SendError(
+            base::StringPrintf("Invalid action '%s' given.", action.c_str()));
   }
 }
 
@@ -3457,7 +3459,7 @@ WebContents* GetWebContentsFromDict(const Browser* browser,
   WebContents* web_contents =
       browser->tab_strip_model()->GetWebContentsAt(tab_index);
   if (!web_contents) {
-    *error_message = StringPrintf("No tab at index %d.", tab_index);
+    *error_message = base::StringPrintf("No tab at index %d.", tab_index);
     return NULL;
   }
   return web_contents;
@@ -3904,7 +3906,7 @@ void TestingAutomationProvider::TriggerBrowserActionById(
   // TODO(kkania): Implement the platform-specific GetExtensionId() in
   // BrowserActionTestUtil.
   if (num_browser_actions != 1) {
-    AutomationJSONReply(this, reply_message).SendError(StringPrintf(
+    AutomationJSONReply(this, reply_message).SendError(base::StringPrintf(
         "Found %d browser actions. Only one browser action must be active.",
         num_browser_actions));
     return;
@@ -4150,7 +4152,7 @@ void TestingAutomationProvider::CloseNotification(
   int balloon_count = static_cast<int>(balloons.size());
   if (index < 0 || index >= balloon_count) {
     AutomationJSONReply(this, reply_message)
-        .SendError(StringPrintf("No notification at index %d", index));
+        .SendError(base::StringPrintf("No notification at index %d", index));
     return;
   }
   std::vector<const Notification*> queued_notes;
@@ -4600,8 +4602,9 @@ void TestingAutomationProvider::LaunchApp(
       id, false  /* do not include disabled extensions */);
   if (!extension) {
     AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Extension with ID '%s' doesn't exist or is disabled.",
-                     id.c_str()));
+        base::StringPrintf(
+            "Extension with ID '%s' doesn't exist or is disabled.",
+            id.c_str()));
     return;
   }
 
@@ -4652,8 +4655,8 @@ void TestingAutomationProvider::SetAppLaunchType(
   const Extension* extension = service->GetExtensionById(
       id, true  /* include disabled extensions */);
   if (!extension) {
-    reply.SendError(
-        StringPrintf("Extension with ID '%s' doesn't exist.", id.c_str()));
+    reply.SendError(base::StringPrintf(
+        "Extension with ID '%s' doesn't exist.", id.c_str()));
     return;
   }
 
@@ -4667,8 +4670,8 @@ void TestingAutomationProvider::SetAppLaunchType(
   } else if (launch_type_str == "window") {
     launch_type = extensions::ExtensionPrefs::LAUNCH_WINDOW;
   } else {
-    reply.SendError(
-        StringPrintf("Unexpected launch type '%s'.", launch_type_str.c_str()));
+    reply.SendError(base::StringPrintf(
+        "Unexpected launch type '%s'.", launch_type_str.c_str()));
     return;
   }
 
@@ -4696,8 +4699,8 @@ void TestingAutomationProvider::GetV8HeapStats(
 
   web_contents = browser->tab_strip_model()->GetWebContentsAt(tab_index);
   if (!web_contents) {
-    AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Could not get WebContents at tab index %d", tab_index));
+    AutomationJSONReply(this, reply_message).SendError(base::StringPrintf(
+        "Could not get WebContents at tab index %d", tab_index));
     return;
   }
 
@@ -4730,8 +4733,8 @@ void TestingAutomationProvider::GetFPS(
 
   web_contents = browser->tab_strip_model()->GetWebContentsAt(tab_index);
   if (!web_contents) {
-    AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Could not get WebContents at tab index %d", tab_index));
+    AutomationJSONReply(this, reply_message).SendError(base::StringPrintf(
+        "Could not get WebContents at tab index %d", tab_index));
     return;
   }
 
@@ -5262,12 +5265,13 @@ void TestingAutomationProvider::ExecuteBrowserCommandAsyncJSON(
     return;
   }
   if (!chrome::SupportsCommand(browser, command)) {
-    reply.SendError(StringPrintf("Browser does not support command=%d.",
-                                 command));
+    reply.SendError(base::StringPrintf("Browser does not support command=%d.",
+                                       command));
     return;
   }
   if (!chrome::IsCommandEnabled(browser, command)) {
-    reply.SendError(StringPrintf("Browser command=%d not enabled.", command));
+    reply.SendError(base::StringPrintf(
+        "Browser command=%d not enabled.", command));
     return;
   }
   chrome::ExecuteCommand(browser, command);
@@ -5291,12 +5295,12 @@ void TestingAutomationProvider::ExecuteBrowserCommandJSON(
   }
   if (!chrome::SupportsCommand(browser, command)) {
     AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Browser does not support command=%d.", command));
+        base::StringPrintf("Browser does not support command=%d.", command));
     return;
   }
   if (!chrome::IsCommandEnabled(browser, command)) {
     AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Browser command=%d not enabled.", command));
+        base::StringPrintf("Browser command=%d not enabled.", command));
     return;
   }
   // First check if we can handle the command without using an observer.
@@ -5313,9 +5317,8 @@ void TestingAutomationProvider::ExecuteBrowserCommandJSON(
     chrome::ExecuteCommand(browser, command);
     return;
   }
-  AutomationJSONReply(this, reply_message).SendError(
-        StringPrintf("Unable to register observer for browser command=%d.",
-                     command));
+  AutomationJSONReply(this, reply_message).SendError(base::StringPrintf(
+      "Unable to register observer for browser command=%d.", command));
 }
 
 void TestingAutomationProvider::IsMenuCommandEnabledJSON(
@@ -5494,8 +5497,8 @@ void TestingAutomationProvider::GetCookiesInBrowserContext(
   automation_util::GetCookies(url, web_contents, &value_size, &value);
   if (value_size == -1) {
     reply.SendError(
-        StringPrintf("Unable to retrieve cookies for url=%s.",
-                     url_string.c_str()));
+        base::StringPrintf("Unable to retrieve cookies for url=%s.",
+                           url_string.c_str()));
     return;
   }
   DictionaryValue dict;
@@ -5536,8 +5539,8 @@ void TestingAutomationProvider::DeleteCookieInBrowserContext(
   automation_util::DeleteCookie(url, cookie_name, web_contents, &success);
   if (!success) {
     reply.SendError(
-        StringPrintf("Failed to delete cookie with name=%s for url=%s.",
-                     cookie_name.c_str(), url_string.c_str()));
+        base::StringPrintf("Failed to delete cookie with name=%s for url=%s.",
+                           cookie_name.c_str(), url_string.c_str()));
     return;
   }
   reply.SendSuccess(NULL);
@@ -5574,8 +5577,8 @@ void TestingAutomationProvider::SetCookieInBrowserContext(
   }
   automation_util::SetCookie(url, value, web_contents, &response_value);
   if (response_value != 1) {
-    reply.SendError(
-        StringPrintf("Unable set cookie for url=%s.", url_string.c_str()));
+    reply.SendError(base::StringPrintf(
+        "Unable set cookie for url=%s.", url_string.c_str()));
     return;
   }
   reply.SendSuccess(NULL);
diff --git a/chrome/browser/automation/testing_automation_provider_chromeos.cc b/chrome/browser/automation/testing_automation_provider_chromeos.cc
index 34f785f..999c28a 100644
--- a/chrome/browser/automation/testing_automation_provider_chromeos.cc
+++ b/chrome/browser/automation/testing_automation_provider_chromeos.cc
@@ -1067,8 +1067,8 @@ void TestingAutomationProvider::ConnectToPrivateNetwork(
   chromeos::VirtualNetwork* network =
       network_library->FindVirtualNetworkByPath(service_path);
   if (!network) {
-    reply.SendError(StringPrintf("No virtual network found: %s",
-                                 service_path.c_str()));
+    reply.SendError(base::StringPrintf("No virtual network found: %s",
+                                       service_path.c_str()));
     return;
   }
   if (network->NeedMoreInfoToConnect()) {
diff --git a/chrome/browser/chromeos/boot_times_loader.cc b/chrome/browser/chromeos/boot_times_loader.cc
index e793013..9beb318 100644
--- a/chrome/browser/chromeos/boot_times_loader.cc
+++ b/chrome/browser/chromeos/boot_times_loader.cc
@@ -359,7 +359,7 @@ void BootTimesLoader::WriteTimes(
       name = tm.name();
     }
     output +=
-        StringPrintf(
+        base::StringPrintf(
             "\n%.2f +%.4f %s",
             since_first.InSecondsF(),
             since_prev.InSecondsF(),
diff --git a/chrome/browser/chromeos/extensions/input_method_apitest_chromeos.cc b/chrome/browser/chromeos/extensions/input_method_apitest_chromeos.cc
index e1173e0..8351cc7 100644
--- a/chrome/browser/chromeos/extensions/input_method_apitest_chromeos.cc
+++ b/chrome/browser/chromeos/extensions/input_method_apitest_chromeos.cc
@@ -46,12 +46,11 @@ class SetInputMethodListener : public content::NotificationObserver {
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE {
     const std::string& content = *content::Details<std::string>(details).ptr();
-    const std::string expected_message = StringPrintf("%s:%s",
-                                                      kSetInputMethodMessage,
-                                                      kNewInputMethod);
+    const std::string expected_message =
+        base::StringPrintf("%s:%s", kSetInputMethodMessage, kNewInputMethod);
     if (content == expected_message) {
       chromeos::input_method::GetInputMethodManager()->
-          ChangeInputMethod(StringPrintf("xkb:%s", kNewInputMethod));
+          ChangeInputMethod(base::StringPrintf("xkb:%s", kNewInputMethod));
 
       extensions::TestSendMessageFunction* function =
           content::Source<extensions::TestSendMessageFunction>(
diff --git a/chrome/browser/chromeos/login/default_user_images.cc b/chrome/browser/chromeos/login/default_user_images.cc
index d2b395b..0c90f13 100644
--- a/chrome/browser/chromeos/login/default_user_images.cc
+++ b/chrome/browser/chromeos/login/default_user_images.cc
@@ -76,7 +76,7 @@ std::string GetDefaultImageString(int index, const std::string& prefix) {
     NOTREACHED();
     return std::string();
   }
-  return StringPrintf("%s%d", prefix.c_str(), index);
+  return base::StringPrintf("%s%d", prefix.c_str(), index);
 }
 
 // Returns true if the string specified consists of the prefix and one of
diff --git a/chrome/browser/chromeos/login/screen_locker_tester.cc b/chrome/browser/chromeos/login/screen_locker_tester.cc
index 620b26b..10c6d18 100644
--- a/chrome/browser/chromeos/login/screen_locker_tester.cc
+++ b/chrome/browser/chromeos/login/screen_locker_tester.cc
@@ -120,7 +120,7 @@ class WebUIScreenLockerTester : public ScreenLockerTester {
 void WebUIScreenLockerTester::SetPassword(const std::string& password) {
   RenderViewHost()->ExecuteJavascriptInWebFrame(
       string16(),
-      ASCIIToUTF16(StringPrintf(
+      ASCIIToUTF16(base::StringPrintf(
           "$('pod-row').pods[0].passwordElement.value = '%s';",
           password.c_str())));
 }
diff --git a/chrome/browser/chromeos/proxy_config_service_impl_unittest.cc b/chrome/browser/chromeos/proxy_config_service_impl_unittest.cc
index a2d11d1..f74df30 100644
--- a/chrome/browser/chromeos/proxy_config_service_impl_unittest.cc
+++ b/chrome/browser/chromeos/proxy_config_service_impl_unittest.cc
@@ -345,7 +345,7 @@ class ProxyConfigServiceImplTest
 
 TEST_F(ProxyConfigServiceImplTest, NetworkProxy) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(tests); ++i) {
-    SCOPED_TRACE(StringPrintf("Test[%" PRIuS "] %s", i,
+    SCOPED_TRACE(base::StringPrintf("Test[%" PRIuS "] %s", i,
                               tests[i].description.c_str()));
 
     ProxyConfigServiceImpl::ProxyConfig test_config;
@@ -363,7 +363,7 @@ TEST_F(ProxyConfigServiceImplTest, NetworkProxy) {
 
 TEST_F(ProxyConfigServiceImplTest, ModifyFromUI) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(tests); ++i) {
-    SCOPED_TRACE(StringPrintf("Test[%" PRIuS "] %s", i,
+    SCOPED_TRACE(base::StringPrintf("Test[%" PRIuS "] %s", i,
                               tests[i].description.c_str()));
 
     // Init with direct.
@@ -484,7 +484,7 @@ TEST_F(ProxyConfigServiceImplTest, DynamicPrefsOverride) {
     const TestParams& recommended_params = tests[proxies[i][1]];
     const TestParams& network_params = tests[proxies[i][2]];
 
-    SCOPED_TRACE(StringPrintf(
+    SCOPED_TRACE(base::StringPrintf(
         "Test[%" PRIuS "] managed=[%s], recommended=[%s], network=[%s]", i,
         managed_params.description.c_str(),
         recommended_params.description.c_str(),
diff --git a/chrome/browser/chromeos/sim_dialog_delegate.cc b/chrome/browser/chromeos/sim_dialog_delegate.cc
index 7ca79eae..61ed45b 100644
--- a/chrome/browser/chromeos/sim_dialog_delegate.cc
+++ b/chrome/browser/chromeos/sim_dialog_delegate.cc
@@ -76,7 +76,8 @@ GURL SimDialogDelegate::GetDialogContentURL() const {
       mode_value = kSimDialogSetLockOnMode;
     else
       mode_value = kSimDialogSetLockOffMode;
-    return GURL(StringPrintf(kSimDialogSpecialModeURL, mode_value.c_str()));
+    return GURL(
+        base::StringPrintf(kSimDialogSpecialModeURL, mode_value.c_str()));
   }
 }
 
diff --git a/chrome/browser/chromeos/status/network_menu.cc b/chrome/browser/chromeos/status/network_menu.cc
index 28d7365..8669ec5 100644
--- a/chrome/browser/chromeos/status/network_menu.cc
+++ b/chrome/browser/chromeos/status/network_menu.cc
@@ -938,7 +938,7 @@ void NetworkMenu::ShowTabbedNetworkSettings(const Network* network) const {
     network_name = l10n_util::GetStringUTF8(
         IDS_STATUSBAR_NETWORK_DEVICE_ETHERNET);
   }
-  std::string page = StringPrintf(
+  std::string page = base::StringPrintf(
       "%s?servicePath=%s&networkType=%d&networkName=%s",
       chrome::kInternetOptionsSubPage,
       net::EscapeUrlEncodedData(network->service_path(), true).c_str(),
diff --git a/chrome/browser/chromeos/system/input_device_settings.cc b/chrome/browser/chromeos/system/input_device_settings.cc
index f5a74fd..14f8378 100644
--- a/chrome/browser/chromeos/system/input_device_settings.cc
+++ b/chrome/browser/chromeos/system/input_device_settings.cc
@@ -65,7 +65,8 @@ void ExecuteScript(int argc, ...) {
 void SetPointerSensitivity(const char* script, int value) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   DCHECK(value > 0 && value < 6);
-  ExecuteScript(3, script, "sensitivity", StringPrintf("%d", value).c_str());
+  ExecuteScript(
+      3, script, "sensitivity", base::StringPrintf("%d", value).c_str());
 }
 
 void SetTPControl(const char* control, bool enabled) {
diff --git a/chrome/browser/component_updater/component_unpacker.cc b/chrome/browser/component_updater/component_unpacker.cc
index c9d4409..9fa9a9c 100644
--- a/chrome/browser/component_updater/component_unpacker.cc
+++ b/chrome/browser/component_updater/component_unpacker.cc
@@ -136,7 +136,8 @@ ComponentUnpacker::ComponentUnpacker(const std::vector<uint8>& pk_hash,
   }
   // We want the temporary directory to be unique and yet predictable, so
   // we can easily find the package in a end user machine.
-  std::string dir(StringPrintf("CRX_%s", base::HexEncode(hash, 6).c_str()));
+  std::string dir(
+      base::StringPrintf("CRX_%s", base::HexEncode(hash, 6).c_str()));
   unpack_path_ = path.DirName().AppendASCII(dir.c_str());
   if (file_util::DirectoryExists(unpack_path_)) {
     if (!file_util::Delete(unpack_path_, true)) {
diff --git a/chrome/browser/component_updater/pepper_flash_component_installer.cc b/chrome/browser/component_updater/pepper_flash_component_installer.cc
index 71edeef..40b3f9c 100644
--- a/chrome/browser/component_updater/pepper_flash_component_installer.cc
+++ b/chrome/browser/component_updater/pepper_flash_component_installer.cc
@@ -150,7 +150,7 @@ bool MakePepperFlashPluginInfo(const base::FilePath& flash_path,
   plugin_info->permissions = kPepperFlashPermissions;
 
   // The description is like "Shockwave Flash 10.2 r154".
-  plugin_info->description = StringPrintf("%s %d.%d r%d",
+  plugin_info->description = base::StringPrintf("%s %d.%d r%d",
       kFlashPluginName, ver_nums[0], ver_nums[1], ver_nums[2]);
 
   plugin_info->version = flash_version.GetString();
diff --git a/chrome/browser/devtools/devtools_window.cc b/chrome/browser/devtools/devtools_window.cc
index e95c54b..976148c 100644
--- a/chrome/browser/devtools/devtools_window.cc
+++ b/chrome/browser/devtools/devtools_window.cc
@@ -611,7 +611,7 @@ void DevToolsWindow::DoAction() {
 std::string SkColorToRGBAString(SkColor color) {
   // We convert the alpha using DoubleToString because StringPrintf will use
   // locale specific formatters (e.g., use , instead of . in German).
-  return StringPrintf("rgba(%d,%d,%d,%s)", SkColorGetR(color),
+  return base::StringPrintf("rgba(%d,%d,%d,%s)", SkColorGetR(color),
       SkColorGetG(color), SkColorGetB(color),
       base::DoubleToString(SkColorGetA(color) / 255.0).c_str());
 }
@@ -632,7 +632,7 @@ GURL DevToolsWindow::GetDevToolsUrl(Profile* profile,
   bool experiments_enabled =
       command_line.HasSwitch(switches::kEnableDevToolsExperiments);
 
-  std::string url_string = StringPrintf("%sdevtools.html?"
+  std::string url_string = base::StringPrintf("%sdevtools.html?"
       "dockSide=%s&toolbarColor=%s&textColor=%s%s%s",
       chrome::kChromeUIDevToolsURL,
       SideToString(dock_side).c_str(),
@@ -651,7 +651,7 @@ void DevToolsWindow::UpdateTheme() {
       tp->GetColor(ThemeProperties::COLOR_TOOLBAR);
   SkColor color_tab_text =
       tp->GetColor(ThemeProperties::COLOR_BOOKMARK_TEXT);
-  std::string command = StringPrintf(
+  std::string command = base::StringPrintf(
       "InspectorFrontendAPI.setToolbarColors(\"%s\", \"%s\")",
       SkColorToRGBAString(color_toolbar).c_str(),
       SkColorToRGBAString(color_tab_text).c_str());
diff --git a/chrome/browser/download/download_browsertest.cc b/chrome/browser/download/download_browsertest.cc
index 20823dc..93defb3 100644
--- a/chrome/browser/download/download_browsertest.cc
+++ b/chrome/browser/download/download_browsertest.cc
@@ -2723,8 +2723,9 @@ IN_PROC_BROWSER_TEST_F(DownloadTest, DownloadTest_Renaming) {
     ASSERT_TRUE(item);
     ASSERT_TRUE(item->IsComplete());
     base::FilePath full_path(item->GetFullPath());
-    EXPECT_EQ(std::string("a_zip_file") + (index == 0 ? std::string(".zip") :
-                                           StringPrintf(" (%d).zip", index)),
+    EXPECT_EQ(std::string("a_zip_file") +
+        (index == 0 ? std::string(".zip") :
+                      base::StringPrintf(" (%d).zip", index)),
               full_path.BaseName().AsUTF8Unsafe());
     ASSERT_TRUE(file_util::PathExists(full_path));
     ASSERT_TRUE(VerifyFile(full_path, origin_contents, origin_contents.size()));
diff --git a/chrome/browser/download/download_path_reservation_tracker_unittest.cc b/chrome/browser/download/download_path_reservation_tracker_unittest.cc
index 6022931..4209317 100644
--- a/chrome/browser/download/download_path_reservation_tracker_unittest.cc
+++ b/chrome/browser/download/download_path_reservation_tracker_unittest.cc
@@ -340,10 +340,12 @@ TEST_F(DownloadPathReservationTrackerTest, UnresolvedConflicts) {
     base::FilePath reserved_path;
     base::FilePath expected_path;
     bool verified = false;
-    if (i > 0)
-      expected_path = path.InsertBeforeExtensionASCII(StringPrintf(" (%d)", i));
-    else
+    if (i > 0) {
+      expected_path =
+          path.InsertBeforeExtensionASCII(base::StringPrintf(" (%d)", i));
+    } else {
       expected_path = path;
+    }
     items[i].reset(CreateDownloadItem(i));
     EXPECT_FALSE(IsPathInUse(expected_path));
     CallGetReservedPath(*items[i], path, true, &reserved_path, &verified);
diff --git a/chrome/browser/extensions/api/declarative/initializing_rules_registry.cc b/chrome/browser/extensions/api/declarative/initializing_rules_registry.cc
index 4ecaf23..0074233 100644
--- a/chrome/browser/extensions/api/declarative/initializing_rules_registry.cc
+++ b/chrome/browser/extensions/api/declarative/initializing_rules_registry.cc
@@ -10,7 +10,7 @@
 
 namespace {
 std::string ToId(int identifier) {
-  return StringPrintf("_%d_", identifier);
+  return base::StringPrintf("_%d_", identifier);
 }
 }  // namespace
 
diff --git a/chrome/browser/extensions/api/declarative/rules_registry_with_cache.cc b/chrome/browser/extensions/api/declarative/rules_registry_with_cache.cc
index b95bc7c..53bcd1f 100644
--- a/chrome/browser/extensions/api/declarative/rules_registry_with_cache.cc
+++ b/chrome/browser/extensions/api/declarative/rules_registry_with_cache.cc
@@ -41,7 +41,7 @@ std::string RulesRegistryWithCache::AddRules(
     const RuleId& rule_id = *((*i)->id);
     RulesDictionaryKey key(extension_id, rule_id);
     if (rules_.find(key) != rules_.end())
-      return StringPrintf(kDuplicateRuleId, rule_id.c_str());
+      return base::StringPrintf(kDuplicateRuleId, rule_id.c_str());
   }
 
   std::string error = AddRulesImpl(extension_id, rules);
diff --git a/chrome/browser/extensions/api/font_settings/font_settings_api.cc b/chrome/browser/extensions/api/font_settings/font_settings_api.cc
index d56ff7fc..0c2b0cb 100644
--- a/chrome/browser/extensions/api/font_settings/font_settings_api.cc
+++ b/chrome/browser/extensions/api/font_settings/font_settings_api.cc
@@ -67,9 +67,9 @@ std::string GetFontNamePrefPath(fonts::GenericFamily generic_family_enum,
   if (script.empty())
     script = prefs::kWebKitCommonScript;
   std::string generic_family = fonts::ToString(generic_family_enum);
-  return StringPrintf(kWebKitFontPrefFormat,
-                      generic_family.c_str(),
-                      script.c_str());
+  return base::StringPrintf(kWebKitFontPrefFormat,
+                            generic_family.c_str(),
+                            script.c_str());
 }
 
 // Returns the localized name of a font so that it can be matched within the
diff --git a/chrome/browser/extensions/api/push_messaging/push_messaging_canary_test.cc b/chrome/browser/extensions/api/push_messaging/push_messaging_canary_test.cc
index 45c25bc..e0eeefa 100644
--- a/chrome/browser/extensions/api/push_messaging/push_messaging_canary_test.cc
+++ b/chrome/browser/extensions/api/push_messaging/push_messaging_canary_test.cc
@@ -93,7 +93,7 @@ class PushMessagingCanaryTest : public ExtensionApiTest {
     const std::string& refresh_token = sync_setup_helper_->refresh_token();
 
     // Construct a JS string to pass in the parameters and start the test.
-    std::string script_string = StringPrintf(
+    std::string script_string = base::StringPrintf(
         "startTestWithCredentials('%s', '%s', '%s');",
         client_id.c_str(), client_secret.c_str(), refresh_token.c_str());
     string16 script16 = UTF8ToUTF16(script_string);
diff --git a/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc b/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
index 0b52d78..259b0f2 100644
--- a/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
+++ b/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
@@ -68,7 +68,7 @@ IN_PROC_BROWSER_TEST_F(TabCaptureApiTest, GetUserMediaTest) {
   int render_process_id = rvh->GetProcess()->GetID();
   int routing_id = rvh->GetRoutingID();
 
-  listener.Reply(StringPrintf("%i:%i", render_process_id, routing_id));
+  listener.Reply(base::StringPrintf("%i:%i", render_process_id, routing_id));
 
   ResultCatcher catcher;
   catcher.RestrictToProfile(browser()->profile());
diff --git a/chrome/browser/extensions/convert_web_app.cc b/chrome/browser/extensions/convert_web_app.cc
index dc65e33..d818a74 100644
--- a/chrome/browser/extensions/convert_web_app.cc
+++ b/chrome/browser/extensions/convert_web_app.cc
@@ -122,9 +122,9 @@ scoped_refptr<Extension> ConvertWebAppToExtension(
   DictionaryValue* icons = new DictionaryValue();
   root->Set(keys::kIcons, icons);
   for (size_t i = 0; i < web_app.icons.size(); ++i) {
-    std::string size = StringPrintf("%i", web_app.icons[i].width);
-    std::string icon_path = StringPrintf("%s/%s.png", kIconsDirName,
-                                         size.c_str());
+    std::string size = base::StringPrintf("%i", web_app.icons[i].width);
+    std::string icon_path = base::StringPrintf("%s/%s.png", kIconsDirName,
+                                               size.c_str());
     icons->SetString(size, icon_path);
   }
 
@@ -163,7 +163,7 @@ scoped_refptr<Extension> ConvertWebAppToExtension(
       continue;
 
     base::FilePath icon_file = icons_dir.AppendASCII(
-        StringPrintf("%i.png", web_app.icons[i].width));
+        base::StringPrintf("%i.png", web_app.icons[i].width));
     std::vector<unsigned char> image_data;
     if (!gfx::PNGCodec::EncodeBGRASkBitmap(web_app.icons[i].data,
                                            false,
diff --git a/chrome/browser/extensions/convert_web_app_unittest.cc b/chrome/browser/extensions/convert_web_app_unittest.cc
index 3305597..5da7064 100644
--- a/chrome/browser/extensions/convert_web_app_unittest.cc
+++ b/chrome/browser/extensions/convert_web_app_unittest.cc
@@ -44,7 +44,7 @@ WebApplicationInfo::IconInfo GetIconInfo(const GURL& url, int size) {
 
   icon_file = icon_file.AppendASCII("extensions")
                        .AppendASCII("convert_web_app")
-                       .AppendASCII(StringPrintf("%i.png", size));
+                       .AppendASCII(base::StringPrintf("%i.png", size));
 
   result.url = url;
   result.width = size;
@@ -120,7 +120,8 @@ TEST_F(ExtensionFromWebApp, Basic) {
 
   const int sizes[] = {16, 48, 128};
   for (size_t i = 0; i < arraysize(sizes); ++i) {
-    GURL icon_url(web_app.app_url.Resolve(StringPrintf("%i.png", sizes[i])));
+    GURL icon_url(
+        web_app.app_url.Resolve(base::StringPrintf("%i.png", sizes[i])));
     web_app.icons.push_back(GetIconInfo(icon_url, sizes[i]));
   }
 
@@ -152,7 +153,7 @@ TEST_F(ExtensionFromWebApp, Basic) {
 
   EXPECT_EQ(web_app.icons.size(), IconsInfo::GetIcons(extension).map().size());
   for (size_t i = 0; i < web_app.icons.size(); ++i) {
-    EXPECT_EQ(StringPrintf("icons/%i.png", web_app.icons[i].width),
+    EXPECT_EQ(base::StringPrintf("icons/%i.png", web_app.icons[i].width),
               IconsInfo::GetIcons(extension).Get(
                   web_app.icons[i].width, ExtensionIconSet::MATCH_EXACTLY));
     ExtensionResource resource = IconsInfo::GetIconResource(
diff --git a/chrome/browser/extensions/extension_browsertest.cc b/chrome/browser/extensions/extension_browsertest.cc
index 9a08f1a..bd255b0 100644
--- a/chrome/browser/extensions/extension_browsertest.cc
+++ b/chrome/browser/extensions/extension_browsertest.cc
@@ -137,7 +137,7 @@ const Extension* ExtensionBrowserTest::LoadExtensionWithFlags(
     const std::vector<extensions::InstallWarning>& install_warnings =
         extension->install_warnings();
     if (!install_warnings.empty()) {
-      std::string install_warnings_message = StringPrintf(
+      std::string install_warnings_message = base::StringPrintf(
           "Unexpected warnings when loading test extension %s:\n",
           path.AsUTF8Unsafe().c_str());
 
diff --git a/chrome/browser/extensions/webstore_inline_installer.cc b/chrome/browser/extensions/webstore_inline_installer.cc
index 1278371..356659c 100644
--- a/chrome/browser/extensions/webstore_inline_installer.cc
+++ b/chrome/browser/extensions/webstore_inline_installer.cc
@@ -147,7 +147,8 @@ bool WebstoreInlineInstaller::IsRequestorURLInVerifiedSite(
   // Turn the verified site (which may be a bare domain, or have a port and/or a
   // path) into a URL that can be parsed by URLPattern.
   std::string verified_site_url =
-      StringPrintf("http://*.%s%s",
+      base::StringPrintf(
+          "http://*.%s%s",
           verified_site.c_str(),
           verified_site.find('/') == std::string::npos ? "/*" : "*");
 
diff --git a/chrome/browser/extensions/webstore_installer.cc b/chrome/browser/extensions/webstore_installer.cc
index 2b5bde6..81db7ed 100644
--- a/chrome/browser/extensions/webstore_installer.cc
+++ b/chrome/browser/extensions/webstore_installer.cc
@@ -126,8 +126,10 @@ void GetDownloadFilePath(
       directory.AppendASCII(id + "_" + random_number + ".crx");
 
   int uniquifier = file_util::GetUniquePathNumber(file, FILE_PATH_LITERAL(""));
-  if (uniquifier > 0)
-    file = file.InsertBeforeExtensionASCII(StringPrintf(" (%d)", uniquifier));
+  if (uniquifier > 0) {
+    file = file.InsertBeforeExtensionASCII(
+        base::StringPrintf(" (%d)", uniquifier));
+  }
 
   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                           base::Bind(callback, file));
diff --git a/chrome/browser/extensions/webstore_startup_installer_browsertest.cc b/chrome/browser/extensions/webstore_startup_installer_browsertest.cc
index 0afb3ca..62ac4f9c 100644
--- a/chrome/browser/extensions/webstore_startup_installer_browsertest.cc
+++ b/chrome/browser/extensions/webstore_startup_installer_browsertest.cc
@@ -82,7 +82,8 @@ class WebstoreStartupInstallerTest : public InProcessBrowserTest {
 
   void RunTest(const std::string& test_function_name) {
     bool result = false;
-    std::string script = StringPrintf("%s('%s')", test_function_name.c_str(),
+    std::string script = base::StringPrintf(
+        "%s('%s')", test_function_name.c_str(),
         test_gallery_url_.c_str());
     ASSERT_TRUE(content::ExecuteScriptAndExtractBool(
         browser()->tab_strip_model()->GetActiveWebContents(),
@@ -100,7 +101,7 @@ class WebstoreStartupInstallerTest : public InProcessBrowserTest {
   bool RunIndexedTest(const std::string& test_function_name,
                       int i) {
     std::string result = "FAILED";
-    std::string script = StringPrintf("%s('%s', %d)",
+    std::string script = base::StringPrintf("%s('%s', %d)",
         test_function_name.c_str(), test_gallery_url_.c_str(), i);
     EXPECT_TRUE(content::ExecuteScriptAndExtractString(
         browser()->tab_strip_model()->GetActiveWebContents(),
diff --git a/chrome/browser/extensions/window_open_apitest.cc b/chrome/browser/extensions/window_open_apitest.cc
index 0a3c8cb..978f77c 100644
--- a/chrome/browser/extensions/window_open_apitest.cc
+++ b/chrome/browser/extensions/window_open_apitest.cc
@@ -63,8 +63,8 @@ bool WaitForTabsAndPopups(Browser* browser,
                           int num_popups,
                           int num_panels) {
   SCOPED_TRACE(
-      StringPrintf("WaitForTabsAndPopups tabs:%d, popups:%d, panels:%d",
-                   num_tabs, num_popups, num_panels));
+      base::StringPrintf("WaitForTabsAndPopups tabs:%d, popups:%d, panels:%d",
+                         num_tabs, num_popups, num_panels));
   // We start with one tab and one browser already open.
   ++num_tabs;
   size_t num_browsers = static_cast<size_t>(num_popups) + 1;
diff --git a/chrome/browser/history/history_unittest.cc b/chrome/browser/history/history_unittest.cc
index fcb8aca..374a6cb 100644
--- a/chrome/browser/history/history_unittest.cc
+++ b/chrome/browser/history/history_unittest.cc
@@ -130,7 +130,8 @@ class HistoryBackendDBTest : public HistoryUnitTestBase {
     base::FilePath data_path;
     ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &data_path));
     data_path = data_path.AppendASCII("History");
-    data_path = data_path.AppendASCII(StringPrintf("history.%d.sql", version));
+    data_path =
+          data_path.AppendASCII(base::StringPrintf("history.%d.sql", version));
     ASSERT_NO_FATAL_FAILURE(
         ExecuteSQLScript(data_path, history_dir_.Append(
             chrome::kHistoryFilename)));
diff --git a/chrome/browser/history/redirect_browsertest.cc b/chrome/browser/history/redirect_browsertest.cc
index b0547de..0f56a71 100644
--- a/chrome/browser/history/redirect_browsertest.cc
+++ b/chrome/browser/history/redirect_browsertest.cc
@@ -122,7 +122,7 @@ IN_PROC_BROWSER_TEST_F(RedirectTest, ClientEmptyReferer) {
   // test server.
   GURL final_url = test_server()->GetURL(std::string());
   ASSERT_TRUE(final_url.is_valid());
-  std::string file_redirect_contents = StringPrintf(
+  std::string file_redirect_contents = base::StringPrintf(
       "<html>"
       "<head></head>"
       "<body onload=\"document.location='%s'\"></body>"
diff --git a/chrome/browser/importer/firefox_importer_utils.cc b/chrome/browser/importer/firefox_importer_utils.cc
index bc86d95..0535cf6 100644
--- a/chrome/browser/importer/firefox_importer_utils.cc
+++ b/chrome/browser/importer/firefox_importer_utils.cc
@@ -56,7 +56,7 @@ base::FilePath GetFirefoxProfilePath() {
 
   base::FilePath source_path;
   for (int i = 0; ; ++i) {
-    std::string current_profile = StringPrintf("Profile%d", i);
+    std::string current_profile = base::StringPrintf("Profile%d", i);
     if (!root.HasKey(current_profile)) {
       // Profiles are continuously numbered. So we exit when we can't
       // find the i-th one.
diff --git a/chrome/browser/media_galleries/media_file_system_registry_unittest.cc b/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
index 97d3fdd..5657f00 100644
--- a/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
+++ b/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
@@ -511,7 +511,7 @@ void ProfileState::CheckGalleries(
   registry->GetMediaFileSystemsForExtension(
       rvh, no_permissions_extension_.get(),
       base::Bind(&ProfileState::CompareResults, base::Unretained(this),
-                 StringPrintf("%s (no permission)", test.c_str()),
+                 base::StringPrintf("%s (no permission)", test.c_str()),
                  base::ConstRef(empty_expectation)));
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(1, GetAndClearComparisonCount());
@@ -520,7 +520,7 @@ void ProfileState::CheckGalleries(
   registry->GetMediaFileSystemsForExtension(
       rvh, regular_permission_extension_.get(),
       base::Bind(&ProfileState::CompareResults, base::Unretained(this),
-                 StringPrintf("%s (regular permission)", test.c_str()),
+                 base::StringPrintf("%s (regular permission)", test.c_str()),
                  base::ConstRef(regular_extension_galleries)));
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(1, GetAndClearComparisonCount());
@@ -529,7 +529,7 @@ void ProfileState::CheckGalleries(
   registry->GetMediaFileSystemsForExtension(
       rvh, all_permission_extension_.get(),
       base::Bind(&ProfileState::CompareResults, base::Unretained(this),
-                 StringPrintf("%s (all permission)", test.c_str()),
+                 base::StringPrintf("%s (all permission)", test.c_str()),
                  base::ConstRef(all_extension_galleries)));
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(1, GetAndClearComparisonCount());
diff --git a/chrome/browser/notifications/notification_object_proxy.cc b/chrome/browser/notifications/notification_object_proxy.cc
index f918724..dd07b51 100644
--- a/chrome/browser/notifications/notification_object_proxy.cc
+++ b/chrome/browser/notifications/notification_object_proxy.cc
@@ -46,8 +46,8 @@ void NotificationObjectProxy::Click() {
 }
 
 std::string NotificationObjectProxy::id() const {
-  return StringPrintf("%d:%d:%d:%d", process_id_, route_id_,
-                      notification_id_, worker_);
+  return base::StringPrintf("%d:%d:%d:%d", process_id_, route_id_,
+                            notification_id_, worker_);
 }
 
 RenderViewHost* NotificationObjectProxy::GetRenderViewHost() const {
diff --git a/chrome/browser/password_manager/native_backend_gnome_x.cc b/chrome/browser/password_manager/native_backend_gnome_x.cc
index ff974cb..5a0b688 100644
--- a/chrome/browser/password_manager/native_backend_gnome_x.cc
+++ b/chrome/browser/password_manager/native_backend_gnome_x.cc
@@ -695,7 +695,7 @@ std::string NativeBackendGnome::GetProfileSpecificAppString() const {
   // Originally, the application string was always just "chrome" and used only
   // so that we had *something* to search for since GNOME Keyring won't search
   // for nothing. Now we use it to distinguish passwords for different profiles.
-  return StringPrintf("%s-%d", kGnomeKeyringAppString, profile_id_);
+  return base::StringPrintf("%s-%d", kGnomeKeyringAppString, profile_id_);
 }
 
 void NativeBackendGnome::MigrateToProfileSpecificLogins() {
diff --git a/chrome/browser/performance_monitor/key_builder.cc b/chrome/browser/performance_monitor/key_builder.cc
index 53b46cd..df740bb 100644
--- a/chrome/browser/performance_monitor/key_builder.cc
+++ b/chrome/browser/performance_monitor/key_builder.cc
@@ -174,46 +174,46 @@ void KeyBuilder::PopulateKeyMaps() {
 }
 
 std::string KeyBuilder::CreateActiveIntervalKey(const base::Time& time) {
-    return StringPrintf("%016" PRId64, time.ToInternalValue());
+    return base::StringPrintf("%016" PRId64, time.ToInternalValue());
 }
 
 std::string KeyBuilder::CreateMetricKey(const base::Time& time,
                                           const MetricType type,
                                           const std::string& activity) {
-  return StringPrintf("%c%c%016" PRId64 "%c%s",
-                      metric_type_to_metric_key_char_[type],
-                      kDelimiter, time.ToInternalValue(),
-                      kDelimiter, activity.c_str());
+  return base::StringPrintf("%c%c%016" PRId64 "%c%s",
+                            metric_type_to_metric_key_char_[type],
+                            kDelimiter, time.ToInternalValue(),
+                            kDelimiter, activity.c_str());
 }
 
 std::string KeyBuilder::CreateEventKey(const base::Time& time,
                                          const EventType type) {
-  return StringPrintf("%016" PRId64 "%c%c",
-                      time.ToInternalValue(), kDelimiter,
-                      event_type_to_event_key_char_[type]);
+  return base::StringPrintf("%016" PRId64 "%c%c",
+                            time.ToInternalValue(), kDelimiter,
+                            event_type_to_event_key_char_[type]);
 }
 
 std::string KeyBuilder::CreateRecentKey(const base::Time& time,
                                           const MetricType type,
                                           const std::string& activity) {
-  return StringPrintf("%016" PRId64 "%c%c%c%s",
-                      time.ToInternalValue(),
-                      kDelimiter, metric_type_to_metric_key_char_[type],
-                      kDelimiter, activity.c_str());
+  return base::StringPrintf("%016" PRId64 "%c%c%c%s",
+                            time.ToInternalValue(),
+                            kDelimiter, metric_type_to_metric_key_char_[type],
+                            kDelimiter, activity.c_str());
 }
 
 std::string KeyBuilder::CreateRecentMapKey(const MetricType type,
                                              const std::string& activity) {
-  return StringPrintf("%s%c%c",
-                      activity.c_str(),
-                      kDelimiter, metric_type_to_metric_key_char_[type]);
+  return base::StringPrintf("%s%c%c",
+                            activity.c_str(),
+                            kDelimiter, metric_type_to_metric_key_char_[type]);
 }
 
 std::string KeyBuilder::CreateMaxValueKey(const MetricType type,
                                             const std::string& activity) {
-  return StringPrintf("%c%c%s",
-                      metric_type_to_metric_key_char_[type],
-                      kDelimiter, activity.c_str());
+  return base::StringPrintf("%c%c%s",
+                            metric_type_to_metric_key_char_[type],
+                            kDelimiter, activity.c_str());
 }
 
 EventType KeyBuilder::EventKeyToEventType(const std::string& event_key) {
diff --git a/chrome/browser/policy/cloud/user_info_fetcher.cc b/chrome/browser/policy/cloud/user_info_fetcher.cc
index 536e788..b51b511 100644
--- a/chrome/browser/policy/cloud/user_info_fetcher.cc
+++ b/chrome/browser/policy/cloud/user_info_fetcher.cc
@@ -22,7 +22,7 @@ static const char kAuthorizationHeaderFormat[] =
     "Authorization: Bearer %s";
 
 static std::string MakeAuthorizationHeader(const std::string& auth_token) {
-  return StringPrintf(kAuthorizationHeaderFormat, auth_token.c_str());
+  return base::StringPrintf(kAuthorizationHeaderFormat, auth_token.c_str());
 }
 
 }  // namespace
diff --git a/chrome/browser/policy/policy_browsertest.cc b/chrome/browser/policy/policy_browsertest.cc
index 8aad6b1..ab39a6b 100644
--- a/chrome/browser/policy/policy_browsertest.cc
+++ b/chrome/browser/policy/policy_browsertest.cc
@@ -1274,7 +1274,7 @@ IN_PROC_BROWSER_TEST_F(PolicyTest, ExtensionInstallForcelist) {
 
   // Setting the forcelist extension should install "good.crx".
   base::ListValue forcelist;
-  forcelist.Append(base::Value::CreateStringValue(StringPrintf(
+  forcelist.Append(base::Value::CreateStringValue(base::StringPrintf(
       "%s;%s", kGoodCrxId, url.spec().c_str())));
   PolicyMap policies;
   policies.Set(key::kExtensionInstallForcelist, POLICY_LEVEL_MANDATORY,
diff --git a/chrome/browser/predictors/autocomplete_action_predictor.cc b/chrome/browser/predictors/autocomplete_action_predictor.cc
index c991975..cc183c36 100644
--- a/chrome/browser/predictors/autocomplete_action_predictor.cc
+++ b/chrome/browser/predictors/autocomplete_action_predictor.cc
@@ -330,8 +330,8 @@ void AutocompleteActionPredictor::OnOmniboxOpenedUrl(
   const AutocompleteMatch& match = log.result.match_at(log.selected_index);
 
   UMA_HISTOGRAM_BOOLEAN(
-      StringPrintf("Prerender.OmniboxNavigationsCouldPrerender%s",
-                   prerender::PrerenderManager::GetModeString()).c_str(),
+      base::StringPrintf("Prerender.OmniboxNavigationsCouldPrerender%s",
+                         prerender::PrerenderManager::GetModeString()).c_str(),
       prerender::IsOmniboxEnabled(profile_));
 
   const GURL& opened_url = match.destination_url;
diff --git a/chrome/browser/prerender/prerender_histograms.cc b/chrome/browser/prerender/prerender_histograms.cc
index 73061c3..d836cf8 100644
--- a/chrome/browser/prerender/prerender_histograms.cc
+++ b/chrome/browser/prerender/prerender_histograms.cc
@@ -162,8 +162,8 @@ void PrerenderHistograms::RecordPrerender(Origin origin, const GURL& url) {
 void PrerenderHistograms::RecordPrerenderStarted(Origin origin) const {
   if (OriginIsOmnibox(origin)) {
     UMA_HISTOGRAM_ENUMERATION(
-        StringPrintf("Prerender.OmniboxPrerenderCount%s",
-                     PrerenderManager::GetModeString()), 1, 2);
+        base::StringPrintf("Prerender.OmniboxPrerenderCount%s",
+                           PrerenderManager::GetModeString()), 1, 2);
   }
 }
 
@@ -171,16 +171,16 @@ void PrerenderHistograms::RecordConcurrency(size_t prerender_count) const {
   static const size_t kMaxRecordableConcurrency = 20;
   DCHECK_GE(kMaxRecordableConcurrency, Config().max_link_concurrency);
   UMA_HISTOGRAM_ENUMERATION(
-      StringPrintf("Prerender.PrerenderCountOf%" PRIuS "Max",
-                   kMaxRecordableConcurrency),
+      base::StringPrintf("Prerender.PrerenderCountOf%" PRIuS "Max",
+                         kMaxRecordableConcurrency),
       prerender_count, kMaxRecordableConcurrency + 1);
 }
 
 void PrerenderHistograms::RecordUsedPrerender(Origin origin) const {
   if (OriginIsOmnibox(origin)) {
     UMA_HISTOGRAM_ENUMERATION(
-        StringPrintf("Prerender.OmniboxNavigationsUsedPrerenderCount%s",
-                     PrerenderManager::GetModeString()), 1, 2);
+        base::StringPrintf("Prerender.OmniboxNavigationsUsedPrerenderCount%s",
+                           PrerenderManager::GetModeString()), 1, 2);
   }
 }
 
diff --git a/chrome/browser/printing/cloud_print/cloud_print_url.cc b/chrome/browser/printing/cloud_print/cloud_print_url.cc
index f710380..ce133f6 100644
--- a/chrome/browser/printing/cloud_print/cloud_print_url.cc
+++ b/chrome/browser/printing/cloud_print/cloud_print_url.cc
@@ -90,7 +90,7 @@ GURL CloudPrintURL::GetCloudPrintServiceEnableURL(
       "/enable_chrome_connector/enable.html");
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("proxy=%s", proxy_id.c_str());
+  std::string query = base::StringPrintf("proxy=%s", proxy_id.c_str());
   replacements.SetQueryStr(query);
   GURL cloud_print_enable_url = cloud_print_service_url.ReplaceComponents(
       replacements);
diff --git a/chrome/browser/profiles/profile_info_cache.cc b/chrome/browser/profiles/profile_info_cache.cc
index 8770f10..18c56a2 100644
--- a/chrome/browser/profiles/profile_info_cache.cc
+++ b/chrome/browser/profiles/profile_info_cache.cc
@@ -710,7 +710,7 @@ int ProfileInfoCache::GetDefaultAvatarIconResourceIDAtIndex(size_t index) {
 // static
 std::string ProfileInfoCache::GetDefaultAvatarIconUrl(size_t index) {
   DCHECK(IsDefaultAvatarIconIndex(index));
-  return StringPrintf("%s%" PRIuS, kDefaultUrlPrefix, index);
+  return base::StringPrintf("%s%" PRIuS, kDefaultUrlPrefix, index);
 }
 
 // static
diff --git a/chrome/browser/profiles/profile_info_cache_unittest.cc b/chrome/browser/profiles/profile_info_cache_unittest.cc
index e7b7fef..b907e35 100644
--- a/chrome/browser/profiles/profile_info_cache_unittest.cc
+++ b/chrome/browser/profiles/profile_info_cache_unittest.cc
@@ -119,8 +119,9 @@ TEST_F(ProfileInfoCacheTest, AddProfiles) {
 
   ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
   for (uint32 i = 0; i < 4; ++i) {
-    base::FilePath profile_path = GetProfilePath(StringPrintf("path_%ud", i));
-    string16 profile_name = ASCIIToUTF16(StringPrintf("name_%ud", i));
+    base::FilePath profile_path =
+        GetProfilePath(base::StringPrintf("path_%ud", i));
+    string16 profile_name = ASCIIToUTF16(base::StringPrintf("name_%ud", i));
     const SkBitmap* icon = rb.GetImageNamed(
         ProfileInfoCache::GetDefaultAvatarIconResourceIDAtIndex(
             i)).ToSkBitmap();
@@ -128,7 +129,7 @@ TEST_F(ProfileInfoCacheTest, AddProfiles) {
     GetCache()->AddProfileToCache(profile_path, profile_name, string16(), i,
                                   false);
     GetCache()->SetBackgroundStatusOfProfileAtIndex(i, true);
-    string16 gaia_name = ASCIIToUTF16(StringPrintf("gaia_%ud", i));
+    string16 gaia_name = ASCIIToUTF16(base::StringPrintf("gaia_%ud", i));
     GetCache()->SetGAIANameOfProfileAtIndex(i, gaia_name);
 
     EXPECT_EQ(i + 1, GetCache()->GetNumberOfProfiles());
@@ -145,13 +146,14 @@ TEST_F(ProfileInfoCacheTest, AddProfiles) {
 
   EXPECT_EQ(4u, GetCache()->GetNumberOfProfiles());
   for (uint32 i = 0; i < 4; ++i) {
-    base::FilePath profile_path = GetProfilePath(StringPrintf("path_%ud", i));
+    base::FilePath profile_path =
+          GetProfilePath(base::StringPrintf("path_%ud", i));
     EXPECT_EQ(i, GetCache()->GetIndexOfProfileWithPath(profile_path));
-    string16 profile_name = ASCIIToUTF16(StringPrintf("name_%ud", i));
+    string16 profile_name = ASCIIToUTF16(base::StringPrintf("name_%ud", i));
     EXPECT_EQ(profile_name, GetCache()->GetNameOfProfileAtIndex(i));
     EXPECT_EQ(i, GetCache()->GetAvatarIconIndexOfProfileAtIndex(i));
     EXPECT_EQ(true, GetCache()->GetBackgroundStatusOfProfileAtIndex(i));
-    string16 gaia_name = ASCIIToUTF16(StringPrintf("gaia_%ud", i));
+    string16 gaia_name = ASCIIToUTF16(base::StringPrintf("gaia_%ud", i));
     EXPECT_EQ(gaia_name, GetCache()->GetGAIANameOfProfileAtIndex(i));
   }
 }
diff --git a/chrome/browser/profiles/profile_io_data.cc b/chrome/browser/profiles/profile_io_data.cc
index 1449f54..35f0a2f 100644
--- a/chrome/browser/profiles/profile_io_data.cc
+++ b/chrome/browser/profiles/profile_io_data.cc
@@ -606,7 +606,7 @@ std::string ProfileIOData::GetSSLSessionCacheShard() {
   // new profile, we'll get a fresh SSL session cache which is separate from
   // the other profiles.
   static unsigned ssl_session_cache_instance = 0;
-  return StringPrintf("profile/%u", ssl_session_cache_instance++);
+  return base::StringPrintf("profile/%u", ssl_session_cache_instance++);
 }
 
 void ProfileIOData::Init(content::ProtocolHandlerMap* protocol_handlers) const {
diff --git a/chrome/browser/safe_browsing/browser_feature_extractor.cc b/chrome/browser/safe_browsing/browser_feature_extractor.cc
index c00d714..9433f89 100644
--- a/chrome/browser/safe_browsing/browser_feature_extractor.cc
+++ b/chrome/browser/safe_browsing/browser_feature_extractor.cc
@@ -59,10 +59,10 @@ static void AddNavigationFeatures(
   NavigationEntry* entry = controller.GetEntryAtIndex(index);
   bool is_secure_referrer = entry->GetReferrer().url.SchemeIsSecure();
   if (!is_secure_referrer) {
-    AddFeature(StringPrintf("%s%s=%s",
-                            feature_prefix.c_str(),
-                            features::kReferrer,
-                            entry->GetReferrer().url.spec().c_str()),
+    AddFeature(base::StringPrintf("%s%s=%s",
+                                  feature_prefix.c_str(),
+                                  features::kReferrer,
+                                  entry->GetReferrer().url.spec().c_str()),
                1.0,
                request);
   }
@@ -102,11 +102,11 @@ static void AddNavigationFeatures(
     if (redirect_chain[i].SchemeIsSecure()) {
       printable_redirect = features::kSecureRedirectValue;
     }
-    AddFeature(StringPrintf("%s%s[%"PRIuS"]=%s",
-                            feature_prefix.c_str(),
-                            features::kRedirect,
-                            i,
-                            printable_redirect.c_str()),
+    AddFeature(base::StringPrintf("%s%s[%"PRIuS"]=%s",
+                                  feature_prefix.c_str(),
+                                  features::kRedirect,
+                                  i,
+                                  printable_redirect.c_str()),
                1.0,
                request);
   }
diff --git a/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc b/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
index c31887e..a9e962a 100644
--- a/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
+++ b/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
@@ -302,19 +302,19 @@ TEST_F(BrowserFeatureExtractorTest, BrowseFeatures) {
   GetFeatureMap(request, &features);
 
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s=%s",
-                                  features::kReferrer,
-                                  "http://google.com/")]);
+            features[base::StringPrintf("%s=%s",
+                                        features::kReferrer,
+                                        "http://google.com/")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s[0]=%s",
-                                  features::kRedirect,
-                                  "http://somerandomwebsite.com/")]);
+            features[base::StringPrintf("%s[0]=%s",
+                                        features::kRedirect,
+                                        "http://somerandomwebsite.com/")]);
   // We shouldn't have a feature for the last redirect in the chain, since it
   // should always be the URL that we navigated to.
   EXPECT_EQ(0.0,
-            features[StringPrintf("%s[1]=%s",
-                                  features::kRedirect,
-                                  "http://foo.com/")]);
+            features[base::StringPrintf("%s[1]=%s",
+                                        features::kRedirect,
+                                        "http://foo.com/")]);
   EXPECT_EQ(0.0, features[features::kHasSSLReferrer]);
   EXPECT_EQ(2.0, features[features::kPageTransitionType]);
   EXPECT_EQ(1.0, features[features::kIsFirstNavigation]);
@@ -341,38 +341,38 @@ TEST_F(BrowserFeatureExtractorTest, BrowseFeatures) {
   GetFeatureMap(request, &features);
 
   EXPECT_EQ(1,
-            features[StringPrintf("%s=%s",
-                                  features::kReferrer,
-                                  "http://www.foo.com/")]);
+            features[base::StringPrintf("%s=%s",
+                                        features::kReferrer,
+                                        "http://www.foo.com/")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s[0]=%s",
-                                  features::kRedirect,
-                                  "http://www.foo.com/redirect")]);
+            features[base::StringPrintf("%s[0]=%s",
+                                        features::kRedirect,
+                                        "http://www.foo.com/redirect")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s[1]=%s",
-                                  features::kRedirect,
-                                  "http://www.foo.com/second_redirect")]);
+            features[base::StringPrintf("%s[1]=%s",
+                                        features::kRedirect,
+                                        "http://www.foo.com/second_redirect")]);
   EXPECT_EQ(0.0, features[features::kHasSSLReferrer]);
   EXPECT_EQ(1.0, features[features::kPageTransitionType]);
   EXPECT_EQ(0.0, features[features::kIsFirstNavigation]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s%s=%s",
-                                  features::kHostPrefix,
-                                  features::kReferrer,
-                                  "http://google.com/")]);
+            features[base::StringPrintf("%s%s=%s",
+                                        features::kHostPrefix,
+                                        features::kReferrer,
+                                        "http://google.com/")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s%s[0]=%s",
-                                  features::kHostPrefix,
-                                  features::kRedirect,
-                                  "http://somerandomwebsite.com/")]);
+            features[base::StringPrintf("%s%s[0]=%s",
+                                        features::kHostPrefix,
+                                        features::kRedirect,
+                                        "http://somerandomwebsite.com/")]);
   EXPECT_EQ(2.0,
-            features[StringPrintf("%s%s",
-                                  features::kHostPrefix,
-                                  features::kPageTransitionType)]);
+            features[base::StringPrintf("%s%s",
+                                        features::kHostPrefix,
+                                        features::kPageTransitionType)]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s%s",
-                                  features::kHostPrefix,
-                                  features::kIsFirstNavigation)]);
+            features[base::StringPrintf("%s%s",
+                                        features::kHostPrefix,
+                                        features::kIsFirstNavigation)]);
   EXPECT_EQ(404.0, features[features::kHttpStatusCode]);
 
   request.Clear();
@@ -394,26 +394,26 @@ TEST_F(BrowserFeatureExtractorTest, BrowseFeatures) {
   GetFeatureMap(request, &features);
 
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s=%s",
-                                  features::kReferrer,
-                                  "http://www.foo.com/page.html")]);
+            features[base::StringPrintf("%s=%s",
+                                        features::kReferrer,
+                                        "http://www.foo.com/page.html")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s[0]=%s",
-                                  features::kRedirect,
-                                  "http://www.foo.com/page.html")]);
+            features[base::StringPrintf("%s[0]=%s",
+                                        features::kRedirect,
+                                        "http://www.foo.com/page.html")]);
   EXPECT_EQ(0.0, features[features::kHasSSLReferrer]);
   EXPECT_EQ(0.0, features[features::kPageTransitionType]);
   EXPECT_EQ(0.0, features[features::kIsFirstNavigation]);
 
   // Should not have host features.
   EXPECT_EQ(0U,
-            features.count(StringPrintf("%s%s",
-                                        features::kHostPrefix,
-                                        features::kPageTransitionType)));
+            features.count(base::StringPrintf("%s%s",
+                                              features::kHostPrefix,
+                                              features::kPageTransitionType)));
   EXPECT_EQ(0U,
-            features.count(StringPrintf("%s%s",
-                                        features::kHostPrefix,
-                                        features::kIsFirstNavigation)));
+            features.count(base::StringPrintf("%s%s",
+                                              features::kHostPrefix,
+                                              features::kIsFirstNavigation)));
 
   request.Clear();
   request.set_url("http://www.bar.com/other_page.html");
@@ -430,30 +430,30 @@ TEST_F(BrowserFeatureExtractorTest, BrowseFeatures) {
   GetFeatureMap(request, &features);
 
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s=%s",
-                                  features::kReferrer,
-                                  "http://www.bar.com/")]);
+            features[base::StringPrintf("%s=%s",
+                                        features::kReferrer,
+                                        "http://www.bar.com/")]);
   EXPECT_EQ(0.0, features[features::kHasSSLReferrer]);
   EXPECT_EQ(0.0, features[features::kPageTransitionType]);
   EXPECT_EQ(0.0, features[features::kIsFirstNavigation]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s%s=%s",
-                                  features::kHostPrefix,
-                                  features::kReferrer,
-                                  "http://www.foo.com/page.html")]);
+            features[base::StringPrintf("%s%s=%s",
+                                        features::kHostPrefix,
+                                        features::kReferrer,
+                                        "http://www.foo.com/page.html")]);
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s%s[0]=%s",
-                                  features::kHostPrefix,
-                                  features::kRedirect,
-                                  "http://www.foo.com/page.html")]);
+            features[base::StringPrintf("%s%s[0]=%s",
+                                        features::kHostPrefix,
+                                        features::kRedirect,
+                                        "http://www.foo.com/page.html")]);
   EXPECT_EQ(0.0,
-            features[StringPrintf("%s%s",
-                                  features::kHostPrefix,
-                                  features::kPageTransitionType)]);
+            features[base::StringPrintf("%s%s",
+                                        features::kHostPrefix,
+                                        features::kPageTransitionType)]);
   EXPECT_EQ(0.0,
-            features[StringPrintf("%s%s",
-                                  features::kHostPrefix,
-                                  features::kIsFirstNavigation)]);
+            features[base::StringPrintf("%s%s",
+                                        features::kHostPrefix,
+                                        features::kIsFirstNavigation)]);
   request.Clear();
   request.set_url("http://www.baz.com/");
   request.set_client_score(0.5);
@@ -475,20 +475,20 @@ TEST_F(BrowserFeatureExtractorTest, BrowseFeatures) {
   GetFeatureMap(request, &features);
 
   EXPECT_EQ(1.0,
-            features[StringPrintf("%s[0]=%s",
-                                  features::kRedirect,
-                                  features::kSecureRedirectValue)]);
+            features[base::StringPrintf("%s[0]=%s",
+                                        features::kRedirect,
+                                        features::kSecureRedirectValue)]);
   EXPECT_EQ(1.0, features[features::kHasSSLReferrer]);
   EXPECT_EQ(5.0, features[features::kPageTransitionType]);
   // Should not have redirect or host features.
   EXPECT_EQ(0U,
-            features.count(StringPrintf("%s%s",
-                                        features::kHostPrefix,
-                                        features::kPageTransitionType)));
+            features.count(base::StringPrintf("%s%s",
+                                              features::kHostPrefix,
+                                              features::kPageTransitionType)));
   EXPECT_EQ(0U,
-            features.count(StringPrintf("%s%s",
-                                        features::kHostPrefix,
-                                        features::kIsFirstNavigation)));
+            features.count(base::StringPrintf("%s%s",
+                                              features::kHostPrefix,
+                                              features::kIsFirstNavigation)));
   EXPECT_EQ(5.0, features[features::kPageTransitionType]);
   EXPECT_EQ(1.0, features[std::string(features::kBadIpFetch) + "193.5.163.8"]);
   EXPECT_FALSE(features.count(std::string(features::kBadIpFetch) +
@@ -511,12 +511,14 @@ TEST_F(BrowserFeatureExtractorTest, SafeBrowsingFeatures) {
   ExtractFeatures(&request);
   std::map<std::string, double> features;
   GetFeatureMap(request, &features);
-  EXPECT_TRUE(features.count(StringPrintf("%s%s",
-                                          features::kSafeBrowsingMaliciousUrl,
-                                          "http://www.malware.com/")));
-  EXPECT_TRUE(features.count(StringPrintf("%s%s",
-                                          features::kSafeBrowsingOriginalUrl,
-                                          "http://www.good.com/")));
+  EXPECT_TRUE(features.count(base::StringPrintf(
+      "%s%s",
+      features::kSafeBrowsingMaliciousUrl,
+      "http://www.malware.com/")));
+  EXPECT_TRUE(features.count(base::StringPrintf(
+      "%s%s",
+       features::kSafeBrowsingOriginalUrl,
+        "http://www.good.com/")));
   EXPECT_DOUBLE_EQ(1.0, features[features::kSafeBrowsingIsSubresource]);
   EXPECT_DOUBLE_EQ(2.0, features[features::kSafeBrowsingThreatType]);
 }
diff --git a/chrome/browser/sessions/persistent_tab_restore_service_browsertest.cc b/chrome/browser/sessions/persistent_tab_restore_service_browsertest.cc
index c39742a..1c6675c 100644
--- a/chrome/browser/sessions/persistent_tab_restore_service_browsertest.cc
+++ b/chrome/browser/sessions/persistent_tab_restore_service_browsertest.cc
@@ -592,8 +592,8 @@ TEST_F(PersistentTabRestoreServiceTest, PruneEntries) {
   for (size_t i = 0; i < max_entries + 5; i++) {
     TabNavigation navigation =
         SessionTypesTestHelper::CreateNavigation(
-            StringPrintf("http://%d", static_cast<int>(i)),
-            StringPrintf("%d", static_cast<int>(i)));
+            base::StringPrintf("http://%d", static_cast<int>(i)),
+            base::StringPrintf("%d", static_cast<int>(i)));
 
     Tab* tab = new Tab();
     tab->navigations.push_back(navigation);
@@ -683,7 +683,8 @@ TEST_F(PersistentTabRestoreServiceTest, PruneIsCalled) {
 
   const size_t max_entries = kMaxEntries;
   for (size_t i = 0; i < max_entries + 5; i++) {
-    NavigateAndCommit(GURL(StringPrintf("http://%d", static_cast<int>(i))));
+    NavigateAndCommit(
+        GURL(base::StringPrintf("http://%d", static_cast<int>(i))));
     service_->CreateHistoricalTab(web_contents(), -1);
   }
 
diff --git a/chrome/browser/ssl/ssl_browser_tests.cc b/chrome/browser/ssl/ssl_browser_tests.cc
index ef253aa..9ead4e6 100644
--- a/chrome/browser/ssl/ssl_browser_tests.cc
+++ b/chrome/browser/ssl/ssl_browser_tests.cc
@@ -576,11 +576,11 @@ IN_PROC_BROWSER_TEST_F(SSLUITest, MAYBE_TestWSSInvalidCertAndClose) {
   watcher.AlsoWaitForTitle(ASCIIToUTF16("FAIL"));
 
   // Create GURLs to test pages.
-  std::string masterUrlPath = StringPrintf("%s?%d",
+  std::string masterUrlPath = base::StringPrintf("%s?%d",
       test_server()->GetURL("files/ssl/wss_close.html").spec().c_str(),
       wss_server_expired_.host_port_pair().port());
   GURL masterUrl(masterUrlPath);
-  std::string slaveUrlPath = StringPrintf("%s?%d",
+  std::string slaveUrlPath = base::StringPrintf("%s?%d",
       test_server()->GetURL("files/ssl/wss_close_slave.html").spec().c_str(),
       wss_server_expired_.host_port_pair().port());
   GURL slaveUrl(slaveUrlPath);
diff --git a/chrome/browser/sync/test/integration/bookmarks_helper.cc b/chrome/browser/sync/test/integration/bookmarks_helper.cc
index 49ca45d..cf4d9dd 100644
--- a/chrome/browser/sync/test/integration/bookmarks_helper.cc
+++ b/chrome/browser/sync/test/integration/bookmarks_helper.cc
@@ -736,23 +736,23 @@ gfx::Image Create1xFaviconFromPNGFile(const std::string& path) {
 }
 
 std::string IndexedURL(int i) {
-  return StringPrintf("http://www.host.ext:1234/path/filename/%d", i);
+  return base::StringPrintf("http://www.host.ext:1234/path/filename/%d", i);
 }
 
 std::wstring IndexedURLTitle(int i) {
-  return StringPrintf(L"URL Title %d", i);
+  return base::StringPrintf(L"URL Title %d", i);
 }
 
 std::wstring IndexedFolderName(int i) {
-  return StringPrintf(L"Folder Name %d", i);
+  return base::StringPrintf(L"Folder Name %d", i);
 }
 
 std::wstring IndexedSubfolderName(int i) {
-  return StringPrintf(L"Subfolder Name %d", i);
+  return base::StringPrintf(L"Subfolder Name %d", i);
 }
 
 std::wstring IndexedSubsubfolderName(int i) {
-  return StringPrintf(L"Subsubfolder Name %d", i);
+  return base::StringPrintf(L"Subsubfolder Name %d", i);
 }
 
 }  // namespace bookmarks_helper
diff --git a/chrome/browser/sync/test/integration/multiple_client_bookmarks_sync_test.cc b/chrome/browser/sync/test/integration/multiple_client_bookmarks_sync_test.cc
index f51e8dc..cb6f8ae 100644
--- a/chrome/browser/sync/test/integration/multiple_client_bookmarks_sync_test.cc
+++ b/chrome/browser/sync/test/integration/multiple_client_bookmarks_sync_test.cc
@@ -24,7 +24,7 @@ IN_PROC_BROWSER_TEST_F(MultipleClientBookmarksSyncTest, Sanity) {
   DisableVerifier();
   for (int i = 0; i < num_clients(); ++i) {
     ASSERT_TRUE(AddURL(i, base::StringPrintf(L"Google URL %d", i),
-        GURL(StringPrintf("http://www.google.com/%d", i))) != NULL);
+        GURL(base::StringPrintf("http://www.google.com/%d", i))) != NULL);
   }
   ASSERT_TRUE(AwaitQuiescence());
   ASSERT_TRUE(AllModelsMatch());
diff --git a/chrome/browser/sync/test/integration/multiple_client_sessions_sync_test.cc b/chrome/browser/sync/test/integration/multiple_client_sessions_sync_test.cc
index a9a4272..ec2b8bb 100644
--- a/chrome/browser/sync/test/integration/multiple_client_sessions_sync_test.cc
+++ b/chrome/browser/sync/test/integration/multiple_client_sessions_sync_test.cc
@@ -46,7 +46,7 @@ IN_PROC_BROWSER_TEST_F(MultipleClientSessionsSyncTest, MAYBE_AllChanged) {
   for (int i = 0; i < num_clients(); ++i) {
     SessionWindowMap windows;
     ASSERT_TRUE(OpenTabAndGetLocalWindows(
-        i, GURL(StringPrintf("http://127.0.0.1/bubba%i", i)), &windows));
+        i, GURL(base::StringPrintf("http://127.0.0.1/bubba%i", i)), &windows));
     client_windows[i].Reset(&windows);
   }
 
@@ -82,7 +82,7 @@ IN_PROC_BROWSER_TEST_F(MultipleClientSessionsSyncTest,
   for (int i = 0; i < num_clients(); ++i) {
     SessionWindowMap windows;
     ASSERT_TRUE(OpenTabAndGetLocalWindows(
-        i, GURL(StringPrintf("http://127.0.0.1/bubba%i", i)), &windows));
+        i, GURL(base::StringPrintf("http://127.0.0.1/bubba%i", i)), &windows));
     client_windows[i].Reset(&windows);
   }
 
diff --git a/chrome/browser/sync/test/integration/performance/autofill_sync_perf_test.cc b/chrome/browser/sync/test/integration/performance/autofill_sync_perf_test.cc
index eae7eef..5168a59 100644
--- a/chrome/browser/sync/test/integration/performance/autofill_sync_perf_test.cc
+++ b/chrome/browser/sync/test/integration/performance/autofill_sync_perf_test.cc
@@ -135,7 +135,7 @@ const std::string AutofillSyncPerfTest::NextGUID() {
 }
 
 const std::string AutofillSyncPerfTest::IntToGUID(int n) {
-  return StringPrintf("00000000-0000-0000-0000-%012X", n);
+  return base::StringPrintf("00000000-0000-0000-0000-%012X", n);
 }
 
 const std::string AutofillSyncPerfTest::NextName() {
@@ -143,7 +143,7 @@ const std::string AutofillSyncPerfTest::NextName() {
 }
 
 const std::string AutofillSyncPerfTest::IntToName(int n) {
-  return StringPrintf("Name%d", n);
+  return base::StringPrintf("Name%d", n);
 }
 
 const std::string AutofillSyncPerfTest::NextValue() {
@@ -151,7 +151,7 @@ const std::string AutofillSyncPerfTest::NextValue() {
 }
 
 const std::string AutofillSyncPerfTest::IntToValue(int n) {
-  return StringPrintf("Value%d", n);
+  return base::StringPrintf("Value%d", n);
 }
 
 void ForceSync(int profile) {
diff --git a/chrome/browser/sync/test/integration/performance/sessions_sync_perf_test.cc b/chrome/browser/sync/test/integration/performance/sessions_sync_perf_test.cc
index 36e6952..affcf86 100644
--- a/chrome/browser/sync/test/integration/performance/sessions_sync_perf_test.cc
+++ b/chrome/browser/sync/test/integration/performance/sessions_sync_perf_test.cc
@@ -112,7 +112,7 @@ GURL SessionsSyncPerfTest::NextURL() {
 }
 
 GURL SessionsSyncPerfTest::IntToURL(int n) {
-  return GURL(StringPrintf("http://localhost/%d", n));
+  return GURL(base::StringPrintf("http://localhost/%d", n));
 }
 
 // TODO(lipalani): Re-enable after crbug.com/96921 is fixed.
diff --git a/chrome/browser/sync/test/integration/performance/typed_urls_sync_perf_test.cc b/chrome/browser/sync/test/integration/performance/typed_urls_sync_perf_test.cc
index af0466d..49e4d8e 100644
--- a/chrome/browser/sync/test/integration/performance/typed_urls_sync_perf_test.cc
+++ b/chrome/browser/sync/test/integration/performance/typed_urls_sync_perf_test.cc
@@ -91,7 +91,7 @@ GURL TypedUrlsSyncPerfTest::NextURL() {
 }
 
 GURL TypedUrlsSyncPerfTest::IntToURL(int n) {
-  return GURL(StringPrintf("http://history%d.google.com/", n));
+  return GURL(base::StringPrintf("http://history%d.google.com/", n));
 }
 
 IN_PROC_BROWSER_TEST_F(TypedUrlsSyncPerfTest, P0) {
diff --git a/chrome/browser/sync/test/integration/two_client_extension_settings_and_app_settings_sync_test.cc b/chrome/browser/sync/test/integration/two_client_extension_settings_and_app_settings_sync_test.cc
index 15683b5..4ff23557 100644
--- a/chrome/browser/sync/test/integration/two_client_extension_settings_and_app_settings_sync_test.cc
+++ b/chrome/browser/sync/test/integration/two_client_extension_settings_and_app_settings_sync_test.cc
@@ -31,27 +31,27 @@ void MutateSomeSettings(
   {
     // Write to extension0 from profile 0 but not profile 1.
     DictionaryValue settings;
-    settings.SetString("asdf", StringPrintf("asdfasdf-%d", seed));
+    settings.SetString("asdf", base::StringPrintf("asdfasdf-%d", seed));
     SetExtensionSettings(test()->verifier(),    extension0, settings);
     SetExtensionSettings(test()->GetProfile(0), extension0, settings);
   }
   {
     // Write the same data to extension1 from both profiles.
     DictionaryValue settings;
-    settings.SetString("asdf", StringPrintf("asdfasdf-%d", seed));
-    settings.SetString("qwer", StringPrintf("qwerqwer-%d", seed));
+    settings.SetString("asdf", base::StringPrintf("asdfasdf-%d", seed));
+    settings.SetString("qwer", base::StringPrintf("qwerqwer-%d", seed));
     SetExtensionSettingsForAllProfiles(extension1, settings);
   }
   {
     // Write different data to extension2 from each profile.
     DictionaryValue settings0;
-    settings0.SetString("zxcv", StringPrintf("zxcvzxcv-%d", seed));
+    settings0.SetString("zxcv", base::StringPrintf("zxcvzxcv-%d", seed));
     SetExtensionSettings(test()->verifier(),    extension2, settings0);
     SetExtensionSettings(test()->GetProfile(0), extension2, settings0);
 
     DictionaryValue settings1;
-    settings1.SetString("1324", StringPrintf("12341234-%d", seed));
-    settings1.SetString("5687", StringPrintf("56785678-%d", seed));
+    settings1.SetString("1324", base::StringPrintf("12341234-%d", seed));
+    settings1.SetString("5687", base::StringPrintf("56785678-%d", seed));
     SetExtensionSettings(test()->verifier(),    extension2, settings1);
     SetExtensionSettings(test()->GetProfile(1), extension2, settings1);
   }
diff --git a/chrome/browser/sync_file_system/drive_file_sync_service_sync_unittest.cc b/chrome/browser/sync_file_system/drive_file_sync_service_sync_unittest.cc
index 45db9f0..69d671d 100644
--- a/chrome/browser/sync_file_system/drive_file_sync_service_sync_unittest.cc
+++ b/chrome/browser/sync_file_system/drive_file_sync_service_sync_unittest.cc
@@ -188,13 +188,15 @@ class DriveFileSyncServiceSyncTest : public testing::Test {
     typedef ResourceIdByTitle::iterator iterator;
     std::pair<iterator, bool> inserted =
         resources_.insert(std::make_pair(title, std::string()));
-    if (inserted.second)
-      inserted.first->second = StringPrintf("%" PRId64, ++resource_count_);
+    if (inserted.second) {
+      inserted.first->second =
+          base::StringPrintf("%" PRId64, ++resource_count_);
+    }
     std::string resource_id = inserted.first->second;
 
     fake_sync_client_->PushRemoteChange(
         kParentResourceId, kAppId, title, resource_id,
-        StringPrintf("%" PRIx64, base::RandUint64()),
+        base::StringPrintf("%" PRIx64, base::RandUint64()),
         false /* deleted */);
     message_loop_.RunUntilIdle();
   }
diff --git a/chrome/browser/themes/theme_syncable_service.cc b/chrome/browser/themes/theme_syncable_service.cc
index a9b2f5c..db3cb96 100644
--- a/chrome/browser/themes/theme_syncable_service.cc
+++ b/chrome/browser/themes/theme_syncable_service.cc
@@ -76,8 +76,8 @@ syncer::SyncMergeResult ThemeSyncableService::MergeDataAndStartSyncing(
   if (initial_sync_data.size() > 1) {
     sync_error_handler_->CreateAndUploadError(
         FROM_HERE,
-        StringPrintf("Received %d theme specifics.",
-                     static_cast<int>(initial_sync_data.size())));
+        base::StringPrintf("Received %d theme specifics.",
+                           static_cast<int>(initial_sync_data.size())));
   }
 
   sync_pb::ThemeSpecifics current_specifics;
diff --git a/chrome/browser/ui/ash/event_rewriter_unittest.cc b/chrome/browser/ui/ash/event_rewriter_unittest.cc
index 0dd9308..b785f85 100644
--- a/chrome/browser/ui/ash/event_rewriter_unittest.cc
+++ b/chrome/browser/ui/ash/event_rewriter_unittest.cc
@@ -52,7 +52,7 @@ std::string GetRewrittenEventAsString(EventRewriter* rewriter,
   InitXKeyEvent(ui_keycode, ui_flags, ui_type, x_keycode, x_state, &xev);
   ui::KeyEvent keyevent(&xev, false /* is_char */);
   rewriter->RewriteForTesting(&keyevent);
-  return StringPrintf(
+  return base::StringPrintf(
       "ui_keycode=%d ui_flags=%d ui_type=%d x_keycode=%u x_state=%u x_type=%d",
       keyevent.key_code(), keyevent.flags(), keyevent.type(),
       xev.xkey.keycode, xev.xkey.state, xev.xkey.type);
@@ -64,7 +64,7 @@ std::string GetExpectedResultAsString(ui::KeyboardCode ui_keycode,
                                       KeyCode x_keycode,
                                       unsigned int x_state,
                                       int x_type) {
-  return StringPrintf(
+  return base::StringPrintf(
       "ui_keycode=%d ui_flags=%d ui_type=%d x_keycode=%u x_state=%u x_type=%d",
       ui_keycode, ui_flags, ui_type, x_keycode, x_state, x_type);
 }
@@ -2354,7 +2354,7 @@ TEST_F(EventRewriterTest, TestRewriteKeyEventSentByXSendEvent) {
     xev.xkey.send_event = True;  // XSendEvent() always does this.
     ui::KeyEvent keyevent(&xev, false /* is_char */);
     rewriter.RewriteForTesting(&keyevent);
-    rewritten_event = StringPrintf(
+    rewritten_event = base::StringPrintf(
         "ui_keycode=%d ui_flags=%d ui_type=%d "
         "x_keycode=%u x_state=%u x_type=%d",
         keyevent.key_code(), keyevent.flags(), keyevent.type(),
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
index 8b7a5d7..be483c1 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
@@ -810,7 +810,7 @@ IN_PROC_BROWSER_TEST_F(LauncherAppBrowserTest, OverflowBubble) {
 
   int items_added = 0;
   while (!test.IsOverflowButtonVisible()) {
-    std::string fake_app_id = StringPrintf("fake_app_%d", items_added);
+    std::string fake_app_id = base::StringPrintf("fake_app_%d", items_added);
     PinFakeApp(fake_app_id);
 
     ++items_added;
diff --git a/chrome/browser/ui/ash/launcher/shell_window_launcher_controller.cc b/chrome/browser/ui/ash/launcher/shell_window_launcher_controller.cc
index bf73768..205079f 100644
--- a/chrome/browser/ui/ash/launcher/shell_window_launcher_controller.cc
+++ b/chrome/browser/ui/ash/launcher/shell_window_launcher_controller.cc
@@ -17,7 +17,7 @@ namespace {
 
 std::string GetAppLauncherId(ShellWindow* shell_window) {
   if (shell_window->window_type_is_panel())
-    return StringPrintf("panel:%d", shell_window->session_id().id());
+    return base::StringPrintf("panel:%d", shell_window->session_id().id());
   return shell_window->extension()->id();
 }
 
diff --git a/chrome/browser/ui/autofill/autofill_dialog_models.cc b/chrome/browser/ui/autofill/autofill_dialog_models.cc
index 65e6c8c..bce0eda 100644
--- a/chrome/browser/ui/autofill/autofill_dialog_models.cc
+++ b/chrome/browser/ui/autofill/autofill_dialog_models.cc
@@ -190,7 +190,7 @@ int MonthComboboxModel::GetItemCount() const {
 
 // static
 string16 MonthComboboxModel::FormatMonth(int index) {
-  return ASCIIToUTF16(StringPrintf("%2d", index));
+  return ASCIIToUTF16(base::StringPrintf("%2d", index));
 }
 
 string16 MonthComboboxModel::GetItemAt(int index) {
diff --git a/chrome/browser/ui/chrome_pages.cc b/chrome/browser/ui/chrome_pages.cc
index b7430330..8d84264 100644
--- a/chrome/browser/ui/chrome_pages.cc
+++ b/chrome/browser/ui/chrome_pages.cc
@@ -42,8 +42,8 @@ void OpenBookmarkManagerWithHash(Browser* browser,
   NavigateParams params(GetSingletonTabNavigateParams(
       browser,
       GURL(kChromeUIBookmarksURL).Resolve(
-      StringPrintf("/#%s%s", action.c_str(),
-      base::Int64ToString(node_id).c_str()))));
+          base::StringPrintf("/#%s%s", action.c_str(),
+              base::Int64ToString(node_id).c_str()))));
   params.path_behavior = NavigateParams::IGNORE_AND_NAVIGATE;
   ShowSingletonTabOverwritingNTP(browser, params);
 }
diff --git a/chrome/browser/ui/views/about_ipc_dialog.cc b/chrome/browser/ui/views/about_ipc_dialog.cc
index 25b100f..f9121db 100644
--- a/chrome/browser/ui/views/about_ipc_dialog.cc
+++ b/chrome/browser/ui/views/about_ipc_dialog.cc
@@ -296,7 +296,7 @@ void AboutIPCDialog::Log(const IPC::LogData& data) {
   if (exploded.hour > 12)
     exploded.hour -= 12;
 
-  std::wstring sent_str = StringPrintf(L"%02d:%02d:%02d.%03d",
+  std::wstring sent_str = base::StringPrintf(L"%02d:%02d:%02d.%03d",
       exploded.hour, exploded.minute, exploded.second, exploded.millisecond);
 
   int count = message_list_.GetItemCount();
@@ -317,13 +317,13 @@ void AboutIPCDialog::Log(const IPC::LogData& data) {
       sent).InMilliseconds();
   // time can go backwards by a few ms (see Time), don't show that.
   time_to_send = std::max(static_cast<int>(time_to_send), 0);
-  std::wstring temp = StringPrintf(L"%d", time_to_send);
+  std::wstring temp = base::StringPrintf(L"%d", time_to_send);
   message_list_.SetItemText(index, kDispatchColumn, temp.c_str());
 
   int64 time_to_process = (base::Time::FromInternalValue(data.dispatch) -
       base::Time::FromInternalValue(data.receive)).InMilliseconds();
   time_to_process = std::max(static_cast<int>(time_to_process), 0);
-  temp = StringPrintf(L"%d", time_to_process);
+  temp = base::StringPrintf(L"%d", time_to_process);
   message_list_.SetItemText(index, kProcessColumn, temp.c_str());
 
   message_list_.SetItemText(index, kParamsColumn,
diff --git a/chrome/browser/ui/views/message_center/web_notification_tray_win_browsertest.cc b/chrome/browser/ui/views/message_center/web_notification_tray_win_browsertest.cc
index fb5b995..a7eaf45 100644
--- a/chrome/browser/ui/views/message_center/web_notification_tray_win_browsertest.cc
+++ b/chrome/browser/ui/views/message_center/web_notification_tray_win_browsertest.cc
@@ -176,7 +176,7 @@ IN_PROC_BROWSER_TEST_F(WebNotificationTrayWinTest,
   size_t notifications_to_add =
       NotificationList::kMaxVisibleMessageCenterNotifications + 1;
   for (size_t i = 0; i < notifications_to_add; ++i) {
-    std::string id = StringPrintf("test_id%d", static_cast<int>(i));
+    std::string id = base::StringPrintf("test_id%d", static_cast<int>(i));
     delegate->AddNotification(id);
   }
   bool shown = tray->message_center_tray_->ShowMessageCenterBubble();
@@ -200,7 +200,7 @@ IN_PROC_BROWSER_TEST_F(WebNotificationTrayWinTest, ManyPopupNotifications) {
   size_t notifications_to_add =
       NotificationList::kMaxVisiblePopupNotifications + 1;
   for (size_t i = 0; i < notifications_to_add; ++i) {
-    std::string id = StringPrintf("test_id%d", static_cast<int>(i));
+    std::string id = base::StringPrintf("test_id%d", static_cast<int>(i));
     delegate->AddNotification(id);
   }
   // Hide and reshow the bubble so that it is updated immediately, not delayed.
diff --git a/chrome/browser/ui/webui/about_ui.cc b/chrome/browser/ui/webui/about_ui.cc
index c3dfe87..5694110 100644
--- a/chrome/browser/ui/webui/about_ui.cc
+++ b/chrome/browser/ui/webui/about_ui.cc
@@ -108,8 +108,8 @@ const char kStringsJsPath[] = "strings.js";
 // redirect solves the problem by eliminating the process transition during the
 // time that about memory is being computed.
 std::string GetAboutMemoryRedirectResponse(Profile* profile) {
-  return StringPrintf("<meta http-equiv=\"refresh\" content=\"0;%s\">",
-                      chrome::kChromeUIMemoryRedirectURL);
+  return base::StringPrintf("<meta http-equiv=\"refresh\" content=\"0;%s\">",
+                            chrome::kChromeUIMemoryRedirectURL);
 }
 
 // Handling about:memory is complicated enough to encapsulate its related
@@ -183,10 +183,10 @@ class ChromeOSTermsHandler
       }
     } else {
       std::string file_path =
-          StringPrintf(chrome::kEULAPathFormat, locale_.c_str());
+          base::StringPrintf(chrome::kEULAPathFormat, locale_.c_str());
       if (!file_util::ReadFileToString(base::FilePath(file_path), &contents_)) {
         // No EULA for given language - try en-US as default.
-        file_path = StringPrintf(chrome::kEULAPathFormat, "en-US");
+        file_path = base::StringPrintf(chrome::kEULAPathFormat, "en-US");
         if (!file_util::ReadFileToString(base::FilePath(file_path),
                                          &contents_)) {
           // File with EULA not found, ResponseOnUIThread will load EULA from
@@ -315,8 +315,9 @@ std::string AddStringRow(const std::string& name, const std::string& value) {
 std::string AboutDiscardsRun() {
   std::string output;
   AppendHeader(&output, 0, "About discards");
-  output.append(StringPrintf("<meta http-equiv=\"refresh\" content=\"2;%s\">",
-                             chrome::kChromeUIDiscardsURL));
+  output.append(
+      base::StringPrintf("<meta http-equiv=\"refresh\" content=\"2;%s\">",
+      chrome::kChromeUIDiscardsURL));
   output.append(WrapWithTag("p", "Discarding a tab..."));
   g_browser_process->oom_priority_manager()->LogMemoryAndDiscardTab();
   AppendFooter(&output);
@@ -348,11 +349,11 @@ std::string AboutDiscards(const std::string& path) {
   } else {
     output.append("<p>None found.  Wait 10 seconds, then refresh.</p>");
   }
-  output.append(StringPrintf("%d discards this session. ",
+  output.append(base::StringPrintf("%d discards this session. ",
                              oom->discard_count()));
-  output.append(StringPrintf("<a href='%s%s'>Discard tab now</a>",
-                             chrome::kChromeUIDiscardsURL,
-                             kRunCommand));
+  output.append(base::StringPrintf("<a href='%s%s'>Discard tab now</a>",
+                                   chrome::kChromeUIDiscardsURL,
+                                   kRunCommand));
 
   base::SystemMemoryInfoKB meminfo;
   base::GetSystemMemoryInfo(&meminfo);
@@ -404,7 +405,7 @@ std::string AboutDiscards(const std::string& path) {
 std::string TransparencyLink(const std::string& label,
                              int value,
                              const std::string& key) {
-  return StringPrintf("<p>%s</p>"
+  return base::StringPrintf("<p>%s</p>"
       "<p>"
       "<a href='%s%s=%d'>--</a> "
       "<a href='%s%s=%d'>-</a> "
@@ -473,7 +474,7 @@ std::string AboutTransparency(const std::string& path) {
   output.append(TransparencyLink("Solo window:",
       TransparencyFromOpacity(ash::FramePainter::kSoloWindowOpacity),
       kSolo));
-  output.append(StringPrintf(
+  output.append(base::StringPrintf(
       "<p>Share: %s%s=%d&%s=%d&%s=%d</p>",
       chrome::kChromeUITransparencyURL,
       kActive,
@@ -688,7 +689,7 @@ std::string AboutStats(const std::string& query) {
   } else if (query == "raw") {
     // Dump the raw counters which have changed in text format.
     data = "<pre>";
-    data.append(StringPrintf("Counter changes in the last %ldms\n",
+    data.append(base::StringPrintf("Counter changes in the last %ldms\n",
         static_cast<long int>(time_since_last_sample.InMilliseconds())));
     for (size_t i = 0; i < counters->GetSize(); ++i) {
       Value* entry = NULL;
diff --git a/chrome/browser/ui/webui/omnibox/omnibox_ui_handler.cc b/chrome/browser/ui/webui/omnibox/omnibox_ui_handler.cc
index 7c43efb..f9c2106 100644
--- a/chrome/browser/ui/webui/omnibox/omnibox_ui_handler.cc
+++ b/chrome/browser/ui/webui/omnibox/omnibox_ui_handler.cc
@@ -97,7 +97,7 @@ void OmniboxUIHandler::AddResultToDictionary(const std::string& prefix,
                                              base::DictionaryValue* output) {
   int i = 0;
   for (; it != end; ++it, ++i) {
-    std::string item_prefix(prefix + StringPrintf(".item_%d", i));
+    std::string item_prefix(prefix + base::StringPrintf(".item_%d", i));
     if (it->provider != NULL) {
       output->SetString(item_prefix + ".provider_name",
                         it->provider->GetName());
diff --git a/chrome/browser/ui/webui/welcome_ui_android.cc b/chrome/browser/ui/webui/welcome_ui_android.cc
index 525284e..0646233 100644
--- a/chrome/browser/ui/webui/welcome_ui_android.cc
+++ b/chrome/browser/ui/webui/welcome_ui_android.cc
@@ -34,7 +34,7 @@ WelcomeUI::WelcomeUI(content::WebUI* web_ui)
   html_source->AddLocalizedString("settings", IDS_FIRSTRUN_SETTINGS_LINK);
 
   std::string locale = g_browser_process->GetApplicationLocale();
-  std::string product_tour_url = StringPrintf(
+  std::string product_tour_url = base::StringPrintf(
       kProductTourBaseURL, locale.c_str());
   html_source->AddString("productTourUrl", product_tour_url);
 
diff --git a/chrome/browser/web_applications/web_app_win.cc b/chrome/browser/web_applications/web_app_win.cc
index 399b086..64b667f 100644
--- a/chrome/browser/web_applications/web_app_win.cc
+++ b/chrome/browser/web_applications/web_app_win.cc
@@ -154,7 +154,7 @@ std::vector<base::FilePath> MatchingShortcutsForProfileAndExtension(
     base::FilePath shortcut_file = base_path;
     if (i) {
       shortcut_file = shortcut_file.InsertBeforeExtensionASCII(
-          StringPrintf(" (%d)", i));
+          base::StringPrintf(" (%d)", i));
     }
     if (file_util::PathExists(shortcut_file) &&
         ShortcutIsForProfile(shortcut_file, profile_path)) {
@@ -281,7 +281,7 @@ bool CreatePlatformShortcuts(
       continue;
     } else if (unique_number > 0) {
       shortcut_file = shortcut_file.InsertBeforeExtensionASCII(
-          StringPrintf(" (%d)", unique_number));
+          base::StringPrintf(" (%d)", unique_number));
     }
 
     base::win::ShortcutProperties shortcut_properties;
diff --git a/chrome/common/cloud_print/cloud_print_helpers.cc b/chrome/common/cloud_print/cloud_print_helpers.cc
index 84e4320..28096c8 100644
--- a/chrome/common/cloud_print/cloud_print_helpers.cc
+++ b/chrome/common/cloud_print/cloud_print_helpers.cc
@@ -76,7 +76,7 @@ GURL GetUrlForPrinterList(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "list"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("proxy=%s", proxy_id.c_str());
+  std::string query = base::StringPrintf("proxy=%s", proxy_id.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
@@ -93,7 +93,7 @@ GURL GetUrlForPrinterUpdate(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "update"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("printerid=%s", printer_id.c_str());
+  std::string query = base::StringPrintf("printerid=%s", printer_id.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
@@ -104,7 +104,7 @@ GURL GetUrlForPrinterDelete(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "delete"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf(
+  std::string query = base::StringPrintf(
       "printerid=%s&reason=%s", printer_id.c_str(), reason.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
@@ -116,7 +116,7 @@ GURL GetUrlForJobFetch(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "fetch"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf(
+  std::string query = base::StringPrintf(
       "printerid=%s&deb=%s", printer_id.c_str(), reason.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
@@ -128,7 +128,7 @@ GURL GetUrlForJobDelete(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "deletejob"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("jobid=%s", job_id.c_str());
+  std::string query = base::StringPrintf("jobid=%s", job_id.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
@@ -139,7 +139,7 @@ GURL GetUrlForJobStatusUpdate(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "control"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf(
+  std::string query = base::StringPrintf(
       "jobid=%s&status=%s", job_id.c_str(), status_string.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
@@ -150,7 +150,7 @@ GURL GetUrlForUserMessage(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "message"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("code=%s", message_id.c_str());
+  std::string query = base::StringPrintf("code=%s", message_id.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
@@ -163,9 +163,9 @@ GURL GetUrlForGetAuthCode(const GURL& cloud_print_server_url,
   std::string path(AppendPathToUrl(cloud_print_server_url, "createrobot"));
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
-  std::string query = StringPrintf("oauth_client_id=%s&proxy=%s",
-                                    oauth_client_id.c_str(),
-                                    proxy_id.c_str());
+  std::string query = base::StringPrintf("oauth_client_id=%s&proxy=%s",
+                                          oauth_client_id.c_str(),
+                                          proxy_id.c_str());
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
@@ -197,15 +197,15 @@ void AddMultipartValueForUpload(const std::string& value_name,
   // First line is the boundary
   post_data->append("--" + mime_boundary + "\r\n");
   // Next line is the Content-disposition
-  post_data->append(StringPrintf("Content-Disposition: form-data; "
+  post_data->append(base::StringPrintf("Content-Disposition: form-data; "
                    "name=\"%s\"\r\n", value_name.c_str()));
   if (!content_type.empty()) {
     // If Content-type is specified, the next line is that
-    post_data->append(StringPrintf("Content-Type: %s\r\n",
+    post_data->append(base::StringPrintf("Content-Type: %s\r\n",
                       content_type.c_str()));
   }
   // Leave an empty line and append the value.
-  post_data->append(StringPrintf("\r\n%s\r\n", value.c_str()));
+  post_data->append(base::StringPrintf("\r\n%s\r\n", value.c_str()));
 }
 
 std::string GetMultipartMimeType(const std::string& mime_boundary) {
@@ -239,12 +239,12 @@ std::string GetPostDataForPrinterTags(
       NOTREACHED();
     }
     // All our tags have a special prefix to identify them as such.
-    std::string msg = StringPrintf("%s%s=%s",
+    std::string msg = base::StringPrintf("%s%s=%s",
         proxy_tag_prefix.c_str(), it->first.c_str(), it->second.c_str());
     AddMultipartValueForUpload(kPrinterTagValue, msg, mime_boundary,
         std::string(), &post_data);
   }
-  std::string tags_hash_msg = StringPrintf("%s=%s",
+  std::string tags_hash_msg = base::StringPrintf("%s=%s",
       tags_hash_tag_name.c_str(),
       HashPrinterTags(printer_tags_prepared).c_str());
   AddMultipartValueForUpload(kPrinterTagValue, tags_hash_msg, mime_boundary,
@@ -253,7 +253,7 @@ std::string GetPostDataForPrinterTags(
 }
 
 std::string GetCloudPrintAuthHeader(const std::string& auth_token) {
-  return StringPrintf("Authorization: OAuth %s", auth_token.c_str());
+  return base::StringPrintf("Authorization: OAuth %s", auth_token.c_str());
 }
 
 }  // namespace cloud_print
diff --git a/chrome/common/cloud_print/cloud_print_helpers_unittest.cc b/chrome/common/cloud_print/cloud_print_helpers_unittest.cc
index cc0f995..abfd001 100644
--- a/chrome/common/cloud_print/cloud_print_helpers_unittest.cc
+++ b/chrome/common/cloud_print/cloud_print_helpers_unittest.cc
@@ -83,7 +83,7 @@ TEST(CloudPrintHelpersTest, GetHashOfPrinterTags) {
   printer_tags["tag2"] = std::string("value2");
 
   chrome::VersionInfo version_info;
-  std::string expected_list_string = StringPrintf(
+  std::string expected_list_string = base::StringPrintf(
       "chrome_version%ssystem_name%ssystem_version%stag1value1tag2value2",
       version_info.CreateVersionString().c_str(),
       base::SysInfo::OperatingSystemName().c_str(),
diff --git a/chrome/common/metrics/variations/uniformity_field_trials.cc b/chrome/common/metrics/variations/uniformity_field_trials.cc
index f208794..b529431 100644
--- a/chrome/common/metrics/variations/uniformity_field_trials.cc
+++ b/chrome/common/metrics/variations/uniformity_field_trials.cc
@@ -28,8 +28,8 @@ void SetupSingleUniformityFieldTrial(
 
   DCHECK_EQ(100 % num_trial_groups, 0);
   const int group_percent = 100 / num_trial_groups;
-  const std::string trial_name = StringPrintf(trial_name_string.c_str(),
-                                              group_percent);
+  const std::string trial_name = base::StringPrintf(trial_name_string.c_str(),
+                                                    group_percent);
 
   DVLOG(1) << "Trial name = " << trial_name;
 
@@ -48,7 +48,8 @@ void SetupSingleUniformityFieldTrial(
   // Loop starts with group 1 because the field trial automatically creates a
   // default group, which would be group 0.
   for (int group_number = 1; group_number < num_trial_groups; ++group_number) {
-    const std::string group_name = StringPrintf("group_%02d", group_number);
+    const std::string group_name =
+          base::StringPrintf("group_%02d", group_number);
     DVLOG(1) << "    Group name = " << group_name;
     trial->AppendGroup(group_name, kProbabilityPerGroup);
     chrome_variations::AssociateGoogleVariationID(
diff --git a/chrome/common/omaha_query_params.cc b/chrome/common/omaha_query_params.cc
index fe59e1c..c13aeda 100644
--- a/chrome/common/omaha_query_params.cc
+++ b/chrome/common/omaha_query_params.cc
@@ -91,12 +91,13 @@ const char* GetChannelString() {
 namespace chrome {
 
 std::string OmahaQueryParams::Get(ProdId prod) {
-  return StringPrintf("os=%s&arch=%s&prod=%s&prodchannel=%s&prodversion=%s",
-                      kOs,
-                      kArch,
-                      GetProdIdString(prod),
-                      GetChannelString(),
-                      chrome::VersionInfo().Version().c_str());
+  return base::StringPrintf(
+      "os=%s&arch=%s&prod=%s&prodchannel=%s&prodversion=%s",
+      kOs,
+      kArch,
+      GetProdIdString(prod),
+      GetChannelString(),
+      chrome::VersionInfo().Version().c_str());
 }
 
 }  // namespace chrome
diff --git a/chrome/common/thumbnail_score.cc b/chrome/common/thumbnail_score.cc
index e2f41a0..ee9a031 100644
--- a/chrome/common/thumbnail_score.cc
+++ b/chrome/common/thumbnail_score.cc
@@ -70,15 +70,16 @@ bool ThumbnailScore::Equals(const ThumbnailScore& rhs) const {
 }
 
 std::string ThumbnailScore::ToString() const {
-  return StringPrintf("boring_score: %f, at_top %d, good_clipping %d, "
-                      "load_completed: %d, "
-                      "time_at_snapshot: %f, redirect_hops_from_dest: %d",
-                      boring_score,
-                      at_top,
-                      good_clipping,
-                      load_completed,
-                      time_at_snapshot.ToDoubleT(),
-                      redirect_hops_from_dest);
+  return base::StringPrintf(
+      "boring_score: %f, at_top %d, good_clipping %d, "
+      "load_completed: %d, "
+      "time_at_snapshot: %f, redirect_hops_from_dest: %d",
+      boring_score,
+      at_top,
+      good_clipping,
+      load_completed,
+      time_at_snapshot.ToDoubleT(),
+      redirect_hops_from_dest);
 }
 
 bool ShouldReplaceThumbnailWith(const ThumbnailScore& current,
diff --git a/chrome/renderer/autofill/form_autofill_browsertest.cc b/chrome/renderer/autofill/form_autofill_browsertest.cc
index 17c91eb..b59850a 100644
--- a/chrome/renderer/autofill/form_autofill_browsertest.cc
+++ b/chrome/renderer/autofill/form_autofill_browsertest.cc
@@ -95,7 +95,7 @@ class FormAutofillTest : public ChromeRenderViewTest {
       expected.value = values[i];
       expected.form_control_type = control_types[i];
       expected.max_length = max_length;
-      SCOPED_TRACE(StringPrintf("i: %" PRIuS, i));
+      SCOPED_TRACE(base::StringPrintf("i: %" PRIuS, i));
       EXPECT_FORM_FIELD_DATA_EQUALS(expected, fields[i]);
     }
   }
diff --git a/chrome/renderer/autofill/password_generation_manager_browsertest.cc b/chrome/renderer/autofill/password_generation_manager_browsertest.cc
index 11747ba..e71b609 100644
--- a/chrome/renderer/autofill/password_generation_manager_browsertest.cc
+++ b/chrome/renderer/autofill/password_generation_manager_browsertest.cc
@@ -82,7 +82,7 @@ class PasswordGenerationManagerTest : public ChromeRenderViewTest {
   void SetNotBlacklistedMessage(const char* form_str) {
     content::PasswordForm form;
     form.origin =
-        GURL(StringPrintf("data:text/html;charset=utf-8,%s", form_str));
+        GURL(base::StringPrintf("data:text/html;charset=utf-8,%s", form_str));
     AutofillMsg_FormNotBlacklisted msg(0, form);
     generation_manager_->OnMessageReceived(msg);
   }
diff --git a/chrome/renderer/printing/print_web_view_helper.cc b/chrome/renderer/printing/print_web_view_helper.cc
index 6c7e00f..f7526be 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -63,7 +63,7 @@ void ExecuteScript(WebKit::WebFrame* frame,
                    const base::Value& parameters) {
   std::string json;
   base::JSONWriter::Write(&parameters, &json);
-  std::string script = StringPrintf(script_format, json.c_str());
+  std::string script = base::StringPrintf(script_format, json.c_str());
   frame->executeScript(WebKit::WebString(UTF8ToUTF16(script)));
 }
 
@@ -438,7 +438,7 @@ void PrintWebViewHelper::PrintHeaderAndFooter(
   options->SetDouble("topMargin", page_layout.margin_top);
   options->SetDouble("bottomMargin", page_layout.margin_bottom);
   options->SetString("pageNumber",
-                     StringPrintf("%d/%d", page_number, total_pages));
+                     base::StringPrintf("%d/%d", page_number, total_pages));
 
   ExecuteScript(frame, kPageSetupScriptFormat, *options);
 
diff --git a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
index 4bd5e90..55d3c12 100644
--- a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
+++ b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
@@ -206,7 +206,7 @@ TEST_F(PhishingTermFeatureExtractorTest, Continuation) {
   // correctly, the extractor has to process the entire string of text.
   string16 page_text(ASCIIToUTF16("one "));
   for (int i = 0; i < 28; ++i) {
-    page_text.append(ASCIIToUTF16(StringPrintf("%d ", i)));
+    page_text.append(ASCIIToUTF16(base::StringPrintf("%d ", i)));
   }
   page_text.append(ASCIIToUTF16("two"));
 
@@ -274,7 +274,7 @@ TEST_F(PhishingTermFeatureExtractorTest, Continuation) {
 TEST_F(PhishingTermFeatureExtractorTest, PartialExtractionTest) {
   scoped_ptr<string16> page_text(new string16(ASCIIToUTF16("one ")));
   for (int i = 0; i < 28; ++i) {
-    page_text->append(ASCIIToUTF16(StringPrintf("%d ", i)));
+    page_text->append(ASCIIToUTF16(base::StringPrintf("%d ", i)));
   }
 
   base::TimeTicks now = base::TimeTicks::Now();
@@ -295,7 +295,7 @@ TEST_F(PhishingTermFeatureExtractorTest, PartialExtractionTest) {
 
   page_text.reset(new string16());
   for (int i = 30; i < 58; ++i) {
-    page_text->append(ASCIIToUTF16(StringPrintf("%d ", i)));
+    page_text->append(ASCIIToUTF16(base::StringPrintf("%d ", i)));
   }
   page_text->append(ASCIIToUTF16("multi word test "));
   features.Clear();
diff --git a/chrome/renderer/searchbox/searchbox_extension.cc b/chrome/renderer/searchbox/searchbox_extension.cc
index 9f5126d..a31b7de 100644
--- a/chrome/renderer/searchbox/searchbox_extension.cc
+++ b/chrome/renderer/searchbox/searchbox_extension.cc
@@ -66,14 +66,14 @@ void Dispatch(WebKit::WebFrame* frame, const WebKit::WebString& script) {
 
 v8::Handle<v8::String> GenerateThumbnailURL(uint64 most_visited_item_id) {
   return UTF8ToV8String(
-      StringPrintf("chrome-search://thumb/%s",
-                   base::Uint64ToString(most_visited_item_id).c_str()));
+      base::StringPrintf("chrome-search://thumb/%s",
+                         base::Uint64ToString(most_visited_item_id).c_str()));
 }
 
 v8::Handle<v8::String> GenerateFaviconURL(uint64 most_visited_item_id) {
   return UTF8ToV8String(
-      StringPrintf("chrome-search://favicon/%s",
-                   base::Uint64ToString(most_visited_item_id).c_str()));
+      base::StringPrintf("chrome-search://favicon/%s",
+                         base::Uint64ToString(most_visited_item_id).c_str()));
 }
 
 const GURL MostVisitedItemIDToURL(
diff --git a/chrome/service/cloud_print/cloud_print_helpers.cc b/chrome/service/cloud_print/cloud_print_helpers.cc
index 6c38a65..3e03e57 100644
--- a/chrome/service/cloud_print/cloud_print_helpers.cc
+++ b/chrome/service/cloud_print/cloud_print_helpers.cc
@@ -52,14 +52,14 @@ GURL GetUrlForJobStatusUpdate(const GURL& cloud_print_server_url,
   GURL::Replacements replacements;
   replacements.SetPathStr(path);
   std::string query =
-      StringPrintf("jobid=%s&status=%s&code=%d&message=%s"
-                   "&numpages=%d&pagesprinted=%d",
-                   job_id.c_str(),
-                   status_string.c_str(),
-                   details.platform_status_flags,
-                   details.status_message.c_str(),
-                   details.total_pages,
-                   details.pages_printed);
+      base::StringPrintf("jobid=%s&status=%s&code=%d&message=%s"
+                         "&numpages=%d&pagesprinted=%d",
+                         job_id.c_str(),
+                         status_string.c_str(),
+                         details.platform_status_flags,
+                         details.status_message.c_str(),
+                         details.total_pages,
+                         details.pages_printed);
   replacements.SetQueryStr(query);
   return cloud_print_server_url.ReplaceComponents(replacements);
 }
diff --git a/chrome/service/cloud_print/cloud_print_helpers_unittest.cc b/chrome/service/cloud_print/cloud_print_helpers_unittest.cc
index a4d7ca0..436a4c9 100644
--- a/chrome/service/cloud_print/cloud_print_helpers_unittest.cc
+++ b/chrome/service/cloud_print/cloud_print_helpers_unittest.cc
@@ -53,7 +53,7 @@ TEST(CloudPrintServiceHelpersTest, GetHashOfPrinterInfo) {
   printer_info.options["tag2"] = std::string("value2");
 
   chrome::VersionInfo version_info;
-  std::string expected_list_string = StringPrintf(
+  std::string expected_list_string = base::StringPrintf(
       "chrome_version%ssystem_name%ssystem_version%stag1value1tag2value2",
       version_info.CreateVersionString().c_str(),
       base::SysInfo::OperatingSystemName().c_str(),
diff --git a/chrome/service/cloud_print/printer_job_handler_unittest.cc b/chrome/service/cloud_print/printer_job_handler_unittest.cc
index b682944..9e19519 100644
--- a/chrome/service/cloud_print/printer_job_handler_unittest.cc
+++ b/chrome/service/cloud_print/printer_job_handler_unittest.cc
@@ -38,6 +38,8 @@ namespace cloud_print {
 
 namespace {
 
+using base::StringPrintf;
+
 const char kExampleCloudPrintServerURL[] = "https://www.google.com/cloudprint/";
 
 const char kExamplePrintTicket[] = "{\"MediaType\":\"plain\","
diff --git a/chrome/test/automation/proxy_launcher.cc b/chrome/test/automation/proxy_launcher.cc
index 8a08b1d..98ba947 100644
--- a/chrome/test/automation/proxy_launcher.cc
+++ b/chrome/test/automation/proxy_launcher.cc
@@ -55,7 +55,7 @@ void UpdateHistoryDates(const base::FilePath& user_data_dir) {
   ASSERT_TRUE(db.Open(history));
   base::Time yesterday = base::Time::Now() - base::TimeDelta::FromDays(1);
   std::string yesterday_str = base::Int64ToString(yesterday.ToInternalValue());
-  std::string query = StringPrintf(
+  std::string query = base::StringPrintf(
       "UPDATE segment_usage "
       "SET time_slot = %s "
       "WHERE id IN (SELECT id FROM segment_usage WHERE time_slot > 0);",
@@ -155,8 +155,9 @@ void ProxyLauncher::CloseBrowserAndServer() {
   // the UI tests in single-process mode.
   // TODO(jhughes): figure out why this is necessary at all, and fix it
   AssertAppNotRunning(
-      StringPrintf("Unable to quit all browser processes. Original PID %d",
-                   process_id_));
+      base::StringPrintf(
+          "Unable to quit all browser processes. Original PID %d",
+          process_id_));
 
   DisconnectFromRunningBrowser();
 }
@@ -315,7 +316,7 @@ void ProxyLauncher::AssertAppNotRunning(const std::string& error_message) {
     final_error_message += " Leftover PIDs: [";
     for (ChromeProcessList::const_iterator it = processes.begin();
          it != processes.end(); ++it) {
-      final_error_message += StringPrintf(" %d", *it);
+      final_error_message += base::StringPrintf(" %d", *it);
     }
     final_error_message += " ]";
   }
diff --git a/chrome/test/base/ui_test_utils.cc b/chrome/test/base/ui_test_utils.cc
index 0a2b555..ccd9bdd 100644
--- a/chrome/test/base/ui_test_utils.cc
+++ b/chrome/test/base/ui_test_utils.cc
@@ -158,7 +158,7 @@ base::FilePath GetSnapshotFileName(const base::FilePath& snapshot_directory) {
   base::Time::Exploded the_time;
 
   base::Time::Now().LocalExplode(&the_time);
-  std::string filename(StringPrintf("%s%04d%02d%02d%02d%02d%02d%s",
+  std::string filename(base::StringPrintf("%s%04d%02d%02d%02d%02d%02d%s",
       kSnapshotBaseName, the_time.year, the_time.month, the_time.day_of_month,
       the_time.hour, the_time.minute, the_time.second, kSnapshotExtension));
 
@@ -168,7 +168,7 @@ base::FilePath GetSnapshotFileName(const base::FilePath& snapshot_directory) {
     std::string suffix;
     base::FilePath trial_file;
     do {
-      suffix = StringPrintf(" (%d)", ++index);
+      suffix = base::StringPrintf(" (%d)", ++index);
       trial_file = snapshot_file.InsertBeforeExtensionASCII(suffix);
     } while (file_util::PathExists(trial_file));
     snapshot_file = trial_file;
diff --git a/chrome/test/perf/url_fetch_test.cc b/chrome/test/perf/url_fetch_test.cc
index 4a88f29..6c8712f 100644
--- a/chrome/test/perf/url_fetch_test.cc
+++ b/chrome/test/perf/url_fetch_test.cc
@@ -73,7 +73,7 @@ class UrlFetchTest : public UIPerfTest {
       ASSERT_TRUE(completed);
     }
     if (var_to_fetch) {
-      std::string script = StringPrintf(
+      std::string script = base::StringPrintf(
           "window.domAutomationController.send(%s);", var_to_fetch);
 
       std::wstring value;
diff --git a/chrome/test/ppapi/ppapi_test.cc b/chrome/test/ppapi/ppapi_test.cc
index fd35776..beecb98 100644
--- a/chrome/test/ppapi/ppapi_test.cc
+++ b/chrome/test/ppapi/ppapi_test.cc
@@ -200,7 +200,7 @@ void PPAPITestBase::RunTestWithSSLServer(const std::string& test_case) {
   uint16_t port = ssl_server.host_port_pair().port();
   RunTestURL(GetTestURL(http_server,
                         test_case,
-                        StringPrintf("ssl_server_port=%d", port)));
+                        base::StringPrintf("ssl_server_port=%d", port)));
 }
 
 void PPAPITestBase::RunTestWithWebSocketServer(const std::string& test_case) {
@@ -223,9 +223,10 @@ void PPAPITestBase::RunTestWithWebSocketServer(const std::string& test_case) {
   uint16_t port = ws_server.host_port_pair().port();
   RunTestURL(GetTestURL(http_server,
                         test_case,
-                        StringPrintf("websocket_host=%s&websocket_port=%d",
-                                     host.c_str(),
-                                     port)));
+                        base::StringPrintf(
+                            "websocket_host=%s&websocket_port=%d",
+                            host.c_str(),
+                            port)));
 }
 
 void PPAPITestBase::RunTestIfAudioOutputAvailable(
@@ -270,7 +271,7 @@ GURL PPAPITestBase::GetTestURL(
     const std::string& extra_params) {
   std::string query = BuildQuery("files/test_case.html?", test_case);
   if (!extra_params.empty())
-    query = StringPrintf("%s&%s", query.c_str(), extra_params.c_str());
+    query = base::StringPrintf("%s&%s", query.c_str(), extra_params.c_str());
 
   return http_server.GetURL(query);
 }
@@ -301,7 +302,7 @@ void PPAPITest::SetUpCommandLine(CommandLine* command_line) {
 
 std::string PPAPITest::BuildQuery(const std::string& base,
                                   const std::string& test_case){
-  return StringPrintf("%stestcase=%s", base.c_str(), test_case.c_str());
+  return base::StringPrintf("%stestcase=%s", base.c_str(), test_case.c_str());
 }
 
 OutOfProcessPPAPITest::OutOfProcessPPAPITest() {
@@ -328,22 +329,22 @@ void PPAPINaClTest::SetUpCommandLine(CommandLine* command_line) {
 // Append the correct mode and testcase string
 std::string PPAPINaClNewlibTest::BuildQuery(const std::string& base,
                                             const std::string& test_case) {
-  return StringPrintf("%smode=nacl_newlib&testcase=%s", base.c_str(),
-                      test_case.c_str());
+  return base::StringPrintf("%smode=nacl_newlib&testcase=%s", base.c_str(),
+                            test_case.c_str());
 }
 
 // Append the correct mode and testcase string
 std::string PPAPINaClGLibcTest::BuildQuery(const std::string& base,
                                            const std::string& test_case) {
-  return StringPrintf("%smode=nacl_glibc&testcase=%s", base.c_str(),
-                      test_case.c_str());
+  return base::StringPrintf("%smode=nacl_glibc&testcase=%s", base.c_str(),
+                            test_case.c_str());
 }
 
 // Append the correct mode and testcase string
 std::string PPAPINaClPNaClTest::BuildQuery(const std::string& base,
                                            const std::string& test_case) {
-  return StringPrintf("%smode=nacl_pnacl&testcase=%s", base.c_str(),
-                      test_case.c_str());
+  return base::StringPrintf("%smode=nacl_pnacl&testcase=%s", base.c_str(),
+                            test_case.c_str());
 }
 
 void PPAPINaClTestDisallowedSockets::SetUpCommandLine(
@@ -363,8 +364,8 @@ void PPAPINaClTestDisallowedSockets::SetUpCommandLine(
 std::string PPAPINaClTestDisallowedSockets::BuildQuery(
     const std::string& base,
     const std::string& test_case) {
-  return StringPrintf("%smode=nacl_newlib&testcase=%s", base.c_str(),
-                      test_case.c_str());
+  return base::StringPrintf("%smode=nacl_newlib&testcase=%s", base.c_str(),
+                            test_case.c_str());
 }
 
 void PPAPIBrokerInfoBarTest::SetUpOnMainThread() {
diff --git a/chrome/test/pyautolib/pyautolib.cc b/chrome/test/pyautolib/pyautolib.cc
index 7724f6f..1822906 100644
--- a/chrome/test/pyautolib/pyautolib.cc
+++ b/chrome/test/pyautolib/pyautolib.cc
@@ -134,8 +134,8 @@ void PyUITestBase::ErrorResponse(
     bool is_timeout,
     std::string* response) {
   base::DictionaryValue error_dict;
-  std::string error_msg = StringPrintf("%s for %s", error_string.c_str(),
-                                       request.c_str());
+  std::string error_msg = base::StringPrintf("%s for %s", error_string.c_str(),
+                                             request.c_str());
   LOG(ERROR) << "Error during automation: " << error_msg;
   error_dict.SetString("error", error_msg);
   error_dict.SetBoolean("is_interface_error", true);
@@ -151,8 +151,8 @@ void PyUITestBase::RequestFailureResponse(
   // TODO(craigdh): Determine timeout directly from IPC's Send().
   if (duration >= timeout) {
     ErrorResponse(
-        StringPrintf("Chrome automation timed out after %d seconds",
-                     static_cast<int>(duration.InSeconds())),
+        base::StringPrintf("Chrome automation timed out after %d seconds",
+                           static_cast<int>(duration.InSeconds())),
         request, true, response);
   } else {
     // TODO(craigdh): Determine specific cause.
diff --git a/chrome/test/reliability/automated_ui_tests.cc b/chrome/test/reliability/automated_ui_tests.cc
index 22266c4..fd50b23 100644
--- a/chrome/test/reliability/automated_ui_tests.cc
+++ b/chrome/test/reliability/automated_ui_tests.cc
@@ -259,7 +259,7 @@ void AutomatedUITest::RunReproduction() {
     LogSuccessResult();
   }
 
-  AppendToTestLog(StringPrintf("total_duration_seconds=%f",
+  AppendToTestLog(base::StringPrintf("total_duration_seconds=%f",
                   CalculateTestDuration(test_start_time_)));
   WriteReportToFile();
 }
@@ -360,7 +360,7 @@ void AutomatedUITest::RunAutomatedUITest() {
     }
   }
 
-  AppendToTestLog(StringPrintf("total_duration_seconds=%f",
+  AppendToTestLog(base::StringPrintf("total_duration_seconds=%f",
                   CalculateTestDuration(test_start_time_)));
 
   // The test is finished so write our report.
diff --git a/chrome/test/reliability/page_load_test.cc b/chrome/test/reliability/page_load_test.cc
index 617ff40..9e6cf7f 100644
--- a/chrome/test/reliability/page_load_test.cc
+++ b/chrome/test/reliability/page_load_test.cc
@@ -458,7 +458,7 @@ class PageLoadTest : public UITest {
         const char* server = g_server_url.empty() ? kDefaultServerUrl :
             g_server_url.c_str();
         std::string test_page_url(
-            StringPrintf("%s/page?id=%d", server, i));
+            base::StringPrintf("%s/page?id=%d", server, i));
         NavigateToURLLogResult(
             test_page_url, log_file, NULL, g_continuous_load, false);
       }
diff --git a/chrome/test/webdriver/webdriver_key_converter.cc b/chrome/test/webdriver/webdriver_key_converter.cc
index 25c8957..e19e9dc 100644
--- a/chrome/test/webdriver/webdriver_key_converter.cc
+++ b/chrome/test/webdriver/webdriver_key_converter.cc
@@ -251,7 +251,7 @@ bool ConvertKeysToWebKeyEvents(const string16& client_keys,
       if (should_skip)
         continue;
       if (key_code == ui::VKEY_UNKNOWN) {
-        *error_msg = StringPrintf(
+        *error_msg = base::StringPrintf(
             "Unknown WebDriver key(%d) at string index (%" PRIuS ")",
             static_cast<int>(key),
             i);
diff --git a/chrome_frame/metrics_service.cc b/chrome_frame/metrics_service.cc
index 73c93b2..cc5e38d 100644
--- a/chrome_frame/metrics_service.cc
+++ b/chrome_frame/metrics_service.cc
@@ -180,12 +180,13 @@ class ChromeFrameMetricsDataUploader : public BSCBImpl {
                                   LPWSTR* additional_headers) {
     std::string new_headers;
     new_headers =
-        StringPrintf("Content-Length: %s\r\n"
-                     "Content-Type: %s\r\n"
-                     "%s\r\n",
-                     base::Int64ToString(upload_data_size_).c_str(),
-                     mime_type_.c_str(),
-                     http_utils::GetDefaultUserAgentHeaderWithCFTag().c_str());
+        base::StringPrintf(
+            "Content-Length: %s\r\n"
+            "Content-Type: %s\r\n"
+            "%s\r\n",
+            base::Int64ToString(upload_data_size_).c_str(),
+            mime_type_.c_str(),
+            http_utils::GetDefaultUserAgentHeaderWithCFTag().c_str());
 
     *additional_headers = reinterpret_cast<wchar_t*>(
         CoTaskMemAlloc((new_headers.size() + 1) * sizeof(wchar_t)));
diff --git a/chrome_frame/test/navigation_test.cc b/chrome_frame/test/navigation_test.cc
index a8f3d40..d59494e 100644
--- a/chrome_frame/test/navigation_test.cc
+++ b/chrome_frame/test/navigation_test.cc
@@ -881,7 +881,7 @@ class HttpHeaderTest : public MockIEEventSinkTest, public testing::Test {
         "Connection: close\r\n"
         "Content-Type: %s\r\n"
         "X-UA-Compatible: chrome=1\r\n";
-    std::string header = StringPrintf(kHeaderFormat, content_type);
+    std::string header = base::StringPrintf(kHeaderFormat, content_type);
     std::wstring url = server_mock_.Resolve(relative_url);
     EXPECT_CALL(server_mock_, Get(_, StrEq(relative_url), _))
         .WillRepeatedly(SendFast(header, data));
diff --git a/chrome_frame/test/test_with_web_server.cc b/chrome_frame/test/test_with_web_server.cc
index 4f786dc..ecb01a7 100644
--- a/chrome_frame/test/test_with_web_server.cc
+++ b/chrome_frame/test/test_with_web_server.cc
@@ -1018,7 +1018,7 @@ TEST_F(ChromeFrameTestWithWebServer, FullTabModeIE_TestDownloadFromForm) {
     virtual bool GetCustomHeaders(std::string* headers) const {
       if (!is_post_)
         return false;
-      *headers = StringPrintf(
+      *headers = base::StringPrintf(
           "HTTP/1.1 200 OK\r\n"
           "Content-Disposition: attachment;filename=\"test.txt\"\r\n"
           "Content-Type: application/text\r\n"
diff --git a/chrome_frame/urlmon_url_request.cc b/chrome_frame/urlmon_url_request.cc
index c5a0a25..a6251bb 100644
--- a/chrome_frame/urlmon_url_request.cc
+++ b/chrome_frame/urlmon_url_request.cc
@@ -1083,7 +1083,7 @@ void UrlmonUrlRequestManager::StartRequestHelper(
     for (size_t i = 0; i < elements->size(); ++i) {
       net::UploadElement* element = (*elements)[i];
       DCHECK(element->type() == net::UploadElement::TYPE_BYTES);
-      std::string chunk_length = StringPrintf(
+      std::string chunk_length = base::StringPrintf(
           "%X\r\n", static_cast<unsigned int>(element->bytes_length()));
       std::vector<char> bytes;
       bytes.insert(bytes.end(), chunk_length.data(),
diff --git a/chromeos/network/geolocation_handler_unittest.cc b/chromeos/network/geolocation_handler_unittest.cc
index dc2cab0..74e86cd 100644
--- a/chromeos/network/geolocation_handler_unittest.cc
+++ b/chromeos/network/geolocation_handler_unittest.cc
@@ -49,8 +49,8 @@ class GeolocationHandlerTest : public testing::Test {
     std::string mac_address =
         base::StringPrintf("%02X:%02X:%02X:%02X:%02X:%02X",
                            idx, 0, 0, 0, 0, 0);
-    std::string channel = StringPrintf("%d", idx);
-    std::string strength = StringPrintf("%d", idx * 10);
+    std::string channel = base::StringPrintf("%d", idx);
+    std::string strength = base::StringPrintf("%d", idx * 10);
     properties.SetStringWithoutPathExpansion(
         shill::kGeoMacAddressProperty, mac_address);
     properties.SetStringWithoutPathExpansion(
diff --git a/chromeos/network/network_event_log.cc b/chromeos/network/network_event_log.cc
index 84d6079..be8d0cb 100644
--- a/chromeos/network/network_event_log.cc
+++ b/chromeos/network/network_event_log.cc
@@ -49,7 +49,7 @@ std::string LogEntry::ToString() const {
   if (!description.empty())
     line += ": " + description;
   if (count > 1)
-    line += StringPrintf(" (%d)", count);
+    line += base::StringPrintf(" (%d)", count);
   line += "\n";
   return line;
 }
diff --git a/chromeos/network/network_event_log_unittest.cc b/chromeos/network/network_event_log_unittest.cc
index 0f20a11..8654bb3 100644
--- a/chromeos/network/network_event_log_unittest.cc
+++ b/chromeos/network/network_event_log_unittest.cc
@@ -98,7 +98,8 @@ TEST_F(NetworkEventLogTest, TestMaxNetworkEvents) {
   const size_t entries_to_add =
       network_event_log::kMaxNetworkEventLogEntries + 3;
   for (size_t i = 0; i < entries_to_add; ++i)
-    network_event_log::AddEntry("test", StringPrintf("event_%"PRIuS, i), "");
+    network_event_log::AddEntry("test",
+                                base::StringPrintf("event_%"PRIuS, i), "");
 
   std::string output = GetAsString(network_event_log::OLDEST_FIRST, 0);
   size_t output_lines = CountLines(output);
diff --git a/chromeos/network/network_state_handler.cc b/chromeos/network/network_state_handler.cc
index d8e0432..d1ca44f 100644
--- a/chromeos/network/network_state_handler.cc
+++ b/chromeos/network/network_state_handler.cc
@@ -57,11 +57,11 @@ std::string ValueAsString(const base::Value& value) {
   } else if (value.GetType() == base::Value::TYPE_INTEGER) {
     int intval = 0;
     value.GetAsInteger(&intval);
-    return StringPrintf("%d", intval);
+    return base::StringPrintf("%d", intval);
   } else if (value.GetType() == base::Value::TYPE_DOUBLE) {
     double dval = 0;
     value.GetAsDouble(&dval);
-    return StringPrintf("%g", dval);
+    return base::StringPrintf("%g", dval);
   } else if (value.GetType() == base::Value::TYPE_STRING) {
     std::string vstr;
     value.GetAsString(&vstr);
@@ -380,7 +380,7 @@ void NetworkStateHandler::UpdateManagedStateProperties(
   }
   network_event_log::AddEntry(
       kLogModule, "PropertiesReceived",
-      StringPrintf("%s (%s)", path.c_str(), managed->name().c_str()));
+      base::StringPrintf("%s (%s)", path.c_str(), managed->name().c_str()));
 }
 
 void NetworkStateHandler::UpdateNetworkServiceProperty(
@@ -447,7 +447,7 @@ void NetworkStateHandler::ManagedStateListChanged(
     // Notify observers that the list of networks has changed.
     network_event_log::AddEntry(
         kLogModule, "NetworkListChanged",
-        StringPrintf("Size: %"PRIuS, network_list_.size()));
+        base::StringPrintf("Size: %"PRIuS, network_list_.size()));
     FOR_EACH_OBSERVER(NetworkStateHandlerObserver, observers_,
                       NetworkListChanged());
     // The list order may have changed, so check if the default network changed.
@@ -456,7 +456,7 @@ void NetworkStateHandler::ManagedStateListChanged(
   } else if (type == ManagedState::MANAGED_TYPE_DEVICE) {
     network_event_log::AddEntry(
         kLogModule, "DeviceListChanged",
-        StringPrintf("Size: %"PRIuS, device_list_.size()));
+        base::StringPrintf("Size: %"PRIuS, device_list_.size()));
     FOR_EACH_OBSERVER(NetworkStateHandlerObserver, observers_,
                       DeviceListChanged());
   } else {
@@ -511,7 +511,7 @@ NetworkStateHandler::ManagedStateList* NetworkStateHandler::GetManagedList(
 void NetworkStateHandler::OnNetworkConnectionStateChanged(
     NetworkState* network) {
   DCHECK(network);
-  std::string desc = StringPrintf(
+  std::string desc = base::StringPrintf(
       "%s: %s", network->path().c_str(), network->connection_state().c_str());
   network_event_log::AddEntry(
       kLogModule, "NetworkConnectionStateChanged", desc);
diff --git a/chromeos/network/network_util.cc b/chromeos/network/network_util.cc
index c0497ad6..fa74068 100644
--- a/chromeos/network/network_util.cc
+++ b/chromeos/network/network_util.cc
@@ -43,7 +43,7 @@ std::string PrefixLengthToNetmask(int32 prefix_length) {
       netmask += ".";
     int value = remainder == 0 ? 0 :
         ((2L << (remainder - 1)) - 1) << (8 - remainder);
-    netmask += StringPrintf("%d", value);
+    netmask += base::StringPrintf("%d", value);
   }
   return netmask;
 }
diff --git a/chromeos/network/shill_property_handler.cc b/chromeos/network/shill_property_handler.cc
index fa01cc9..0e3c77a8 100644
--- a/chromeos/network/shill_property_handler.cc
+++ b/chromeos/network/shill_property_handler.cc
@@ -320,7 +320,7 @@ void ShillPropertyHandler::UpdateAvailableTechnologies(
   available_technologies_.clear();
   network_event_log::AddEntry(
       kLogModule, "AvailableTechnologiesChanged",
-      StringPrintf("Size: %"PRIuS, technologies.GetSize()));
+      base::StringPrintf("Size: %"PRIuS, technologies.GetSize()));
   for (base::ListValue::const_iterator iter = technologies.begin();
        iter != technologies.end(); ++iter) {
     std::string technology;
@@ -335,7 +335,7 @@ void ShillPropertyHandler::UpdateEnabledTechnologies(
   enabled_technologies_.clear();
   network_event_log::AddEntry(
       kLogModule, "EnabledTechnologiesChanged",
-      StringPrintf("Size: %"PRIuS, technologies.GetSize()));
+      base::StringPrintf("Size: %"PRIuS, technologies.GetSize()));
   for (base::ListValue::const_iterator iter = technologies.begin();
        iter != technologies.end(); ++iter) {
     std::string technology;
@@ -350,7 +350,7 @@ void ShillPropertyHandler::UpdateUninitializedTechnologies(
   uninitialized_technologies_.clear();
   network_event_log::AddEntry(
       kLogModule, "UninitializedTechnologiesChanged",
-      StringPrintf("Size: %"PRIuS, technologies.GetSize()));
+      base::StringPrintf("Size: %"PRIuS, technologies.GetSize()));
   for (base::ListValue::const_iterator iter = technologies.begin();
        iter != technologies.end(); ++iter) {
     std::string technology;
diff --git a/components/autofill/browser/autofill_manager_unittest.cc b/components/autofill/browser/autofill_manager_unittest.cc
index 52d3225..2ab780d 100644
--- a/components/autofill/browser/autofill_manager_unittest.cc
+++ b/components/autofill/browser/autofill_manager_unittest.cc
@@ -305,7 +305,7 @@ void ExpectSuggestions(int page_id,
   ASSERT_EQ(expected_num_suggestions, icons.size());
   ASSERT_EQ(expected_num_suggestions, unique_ids.size());
   for (size_t i = 0; i < expected_num_suggestions; ++i) {
-    SCOPED_TRACE(StringPrintf("i: %" PRIuS, i));
+    SCOPED_TRACE(base::StringPrintf("i: %" PRIuS, i));
     EXPECT_EQ(expected_values[i], values[i]);
     EXPECT_EQ(expected_labels[i], labels[i]);
     EXPECT_EQ(expected_icons[i], icons[i]);
@@ -511,8 +511,9 @@ class TestAutofillManager : public AutofillManager {
                 submitted_form->field_count());
       for (size_t i = 0; i < expected_submitted_field_types_.size(); ++i) {
         SCOPED_TRACE(
-            StringPrintf("Field %d with value %s", static_cast<int>(i),
-                         UTF16ToUTF8(submitted_form->field(i)->value).c_str()));
+            base::StringPrintf(
+                "Field %d with value %s", static_cast<int>(i),
+                UTF16ToUTF8(submitted_form->field(i)->value).c_str()));
         const FieldTypeSet& possible_types =
             submitted_form->field(i)->possible_types();
         EXPECT_EQ(expected_submitted_field_types_[i].size(),
diff --git a/components/autofill/browser/wallet/encryption_escrow_client.cc b/components/autofill/browser/wallet/encryption_escrow_client.cc
index e41014d..cf7d21d 100644
--- a/components/autofill/browser/wallet/encryption_escrow_client.cc
+++ b/components/autofill/browser/wallet/encryption_escrow_client.cc
@@ -60,7 +60,7 @@ void EncryptionEscrowClient::EncryptOneTimePad(
 
   request_type_ = ENCRYPT_ONE_TIME_PAD;
 
-  std::string post_body = StringPrintf(
+  std::string post_body = base::StringPrintf(
       kEncryptOtpBodyFormat,
       base::HexEncode(&num_bits, 1).c_str(),
       base::HexEncode(&(one_time_pad[0]), one_time_pad.size()).c_str());
@@ -81,7 +81,7 @@ void EncryptionEscrowClient::EscrowInstrumentInformation(
       net::EscapeUrlEncodedData(
           UTF16ToUTF8(new_instrument.card_verification_number()), true);
 
-  std::string post_body = StringPrintf(
+  std::string post_body = base::StringPrintf(
       kEscrowInstrumentInformationFormat,
       obfuscated_gaia_id.c_str(),
       primary_account_number.c_str(),
@@ -96,7 +96,7 @@ void EncryptionEscrowClient::EscrowCardVerificationNumber(
   DCHECK_EQ(NO_PENDING_REQUEST, request_type_);
   request_type_ = ESCROW_CARD_VERIFICATION_NUMBER;
 
-  std::string post_body = StringPrintf(
+  std::string post_body = base::StringPrintf(
       kEscrowCardVerficationNumberFormat,
       obfuscated_gaia_id.c_str(),
       card_verification_number.c_str());
diff --git a/components/visitedlink/test/visitedlink_unittest.cc b/components/visitedlink/test/visitedlink_unittest.cc
index ff54743..4bdadf4 100644
--- a/components/visitedlink/test/visitedlink_unittest.cc
+++ b/components/visitedlink/test/visitedlink_unittest.cc
@@ -44,7 +44,7 @@ const int g_test_count = 1000;
 
 // Returns a test URL for index |i|
 GURL TestURL(int i) {
-  return GURL(StringPrintf("%s%d", g_test_prefix, i));
+  return GURL(base::StringPrintf("%s%d", g_test_prefix, i));
 }
 
 std::vector<VisitedLinkSlave*> g_slaves;
diff --git a/content/app/content_main_runner.cc b/content/app/content_main_runner.cc
index e0a5a99..50930fa 100644
--- a/content/app/content_main_runner.cc
+++ b/content/app/content_main_runner.cc
@@ -196,8 +196,9 @@ void SendTaskPortToParentProcess() {
   base::MachPortSender child_sender(mach_port_name.c_str());
   kern_return_t err = child_sender.SendMessage(child_message, kTimeoutMs);
   if (err != KERN_SUCCESS) {
-    LOG(ERROR) << StringPrintf("child SendMessage() failed: 0x%x %s", err,
-                               mach_error_string(err));
+    LOG(ERROR) <<
+        base::StringPrintf("child SendMessage() failed: 0x%x %s", err,
+                           mach_error_string(err));
   }
 }
 
diff --git a/content/browser/accessibility/accessibility_tree_formatter_win.cc b/content/browser/accessibility/accessibility_tree_formatter_win.cc
index bf7495f..389c0e5 100644
--- a/content/browser/accessibility/accessibility_tree_formatter_win.cc
+++ b/content/browser/accessibility/accessibility_tree_formatter_win.cc
@@ -90,13 +90,13 @@ string16 AccessibilityTreeFormatter::ToString(
   Add(false, L"role_name='" + acc_obj->role_name() + L"'");
   VARIANT currentValue;
   if (acc_obj->get_currentValue(&currentValue) == S_OK)
-    Add(false, StringPrintf(L"currentValue=%.2f", V_R8(&currentValue)));
+    Add(false, base::StringPrintf(L"currentValue=%.2f", V_R8(&currentValue)));
   VARIANT minimumValue;
   if (acc_obj->get_minimumValue(&minimumValue) == S_OK)
-    Add(false, StringPrintf(L"minimumValue=%.2f", V_R8(&minimumValue)));
+    Add(false, base::StringPrintf(L"minimumValue=%.2f", V_R8(&minimumValue)));
   VARIANT maximumValue;
   if (acc_obj->get_maximumValue(&maximumValue) == S_OK)
-    Add(false, StringPrintf(L"maximumValue=%.2f", V_R8(&maximumValue)));
+    Add(false, base::StringPrintf(L"maximumValue=%.2f", V_R8(&maximumValue)));
   Add(false, L"description='" + description + L"'");
   Add(false, L"default_action='" + default_action + L"'");
   Add(false, L"keyboard_shortcut='" + keyboard_shortcut + L"'");
@@ -107,51 +107,51 @@ string16 AccessibilityTreeFormatter::ToString(
           &left, &top, &width, &height, variant_self) &&
       S_FALSE != root->ToBrowserAccessibilityWin()->accLocation(
           &root_left, &root_top, &root_width, &root_height, variant_self)) {
-    Add(false, StringPrintf(L"location=(%d, %d)",
+    Add(false, base::StringPrintf(L"location=(%d, %d)",
             left - root_left, top - root_top));
-    Add(false, StringPrintf(L"size=(%d, %d)", width, height));
+    Add(false, base::StringPrintf(L"size=(%d, %d)", width, height));
   }
   LONG index_in_parent;
   if (acc_obj->get_indexInParent(&index_in_parent) == S_OK)
-    Add(false, StringPrintf(L"index_in_parent=%d", index_in_parent));
+    Add(false, base::StringPrintf(L"index_in_parent=%d", index_in_parent));
   LONG n_relations;
   if (acc_obj->get_nRelations(&n_relations) == S_OK)
-    Add(false, StringPrintf(L"n_relations=%d", n_relations));
+    Add(false, base::StringPrintf(L"n_relations=%d", n_relations));
   LONG group_level, similar_items_in_group, position_in_group;
   if (acc_obj->get_groupPosition(&group_level,
                                  &similar_items_in_group,
                                  &position_in_group) == S_OK) {
-    Add(false, StringPrintf(L"group_level=%d", group_level));
-    Add(false, StringPrintf(L"similar_items_in_group=%d",
+    Add(false, base::StringPrintf(L"group_level=%d", group_level));
+    Add(false, base::StringPrintf(L"similar_items_in_group=%d",
                             similar_items_in_group));
-    Add(false, StringPrintf(L"position_in_group=%d", position_in_group));
+    Add(false, base::StringPrintf(L"position_in_group=%d", position_in_group));
   }
   LONG table_rows;
   if (acc_obj->get_nRows(&table_rows) == S_OK)
-    Add(false, StringPrintf(L"table_rows=%d", table_rows));
+    Add(false, base::StringPrintf(L"table_rows=%d", table_rows));
   LONG table_columns;
   if (acc_obj->get_nRows(&table_columns) == S_OK)
-    Add(false, StringPrintf(L"table_columns=%d", table_columns));
+    Add(false, base::StringPrintf(L"table_columns=%d", table_columns));
   LONG row_index;
   if (acc_obj->get_rowIndex(&row_index) == S_OK)
-    Add(false, StringPrintf(L"row_index=%d", row_index));
+    Add(false, base::StringPrintf(L"row_index=%d", row_index));
   LONG column_index;
   if (acc_obj->get_columnIndex(&column_index) == S_OK)
-    Add(false, StringPrintf(L"column_index=%d", column_index));
+    Add(false, base::StringPrintf(L"column_index=%d", column_index));
   LONG n_characters;
   if (acc_obj->get_nCharacters(&n_characters) == S_OK)
-    Add(false, StringPrintf(L"n_characters=%d", n_characters));
+    Add(false, base::StringPrintf(L"n_characters=%d", n_characters));
   LONG caret_offset;
   if (acc_obj->get_caretOffset(&caret_offset) == S_OK)
-    Add(false, StringPrintf(L"caret_offset=%d", caret_offset));
+    Add(false, base::StringPrintf(L"caret_offset=%d", caret_offset));
   LONG n_selections;
   if (acc_obj->get_nSelections(&n_selections) == S_OK) {
-    Add(false, StringPrintf(L"n_selections=%d", n_selections));
+    Add(false, base::StringPrintf(L"n_selections=%d", n_selections));
     if (n_selections > 0) {
       LONG start, end;
       if (acc_obj->get_selection(0, &start, &end) == S_OK) {
-        Add(false, StringPrintf(L"selection_start=%d", start));
-        Add(false, StringPrintf(L"selection_end=%d", end));
+        Add(false, base::StringPrintf(L"selection_start=%d", start));
+        Add(false, base::StringPrintf(L"selection_end=%d", end));
       }
     }
   }
diff --git a/content/browser/browser_plugin/browser_plugin_host_browsertest.cc b/content/browser/browser_plugin/browser_plugin_host_browsertest.cc
index 25ca4e6..66dd8aa 100644
--- a/content/browser/browser_plugin/browser_plugin_host_browsertest.cc
+++ b/content/browser/browser_plugin/browser_plugin_host_browsertest.cc
@@ -95,7 +95,7 @@ const char kHTMLForGuestWithSize[] =
     "</html>";
 
 std::string GetHTMLForGuestWithTitle(const std::string& title) {
-  return StringPrintf(kHTMLForGuestWithTitle, title.c_str());
+  return base::StringPrintf(kHTMLForGuestWithTitle, title.c_str());
 }
 
 }  // namespace
@@ -327,10 +327,10 @@ class BrowserPluginHostTest : public ContentBrowserTest {
     if (!is_guest_data_url) {
       test_url = test_server()->GetURL(guest_url);
       ExecuteSyncJSFunction(
-          rvh, StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
+          rvh, base::StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
     } else {
       ExecuteSyncJSFunction(
-          rvh, StringPrintf("SetSrc('%s');", guest_url.c_str()));
+          rvh, base::StringPrintf("SetSrc('%s');", guest_url.c_str()));
     }
 
     // Wait to make sure embedder is created/attached to WebContents.
@@ -397,7 +397,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest,
     int spin_time = 10 * TestTimeouts::tiny_timeout().InMilliseconds();
     ExecuteSyncJSFunction(
         test_guest()->web_contents()->GetRenderViewHost(),
-        StringPrintf("StartPauseMs(%d);", spin_time).c_str());
+        base::StringPrintf("StartPauseMs(%d);", spin_time).c_str());
 
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
@@ -439,8 +439,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest,
 // sample guest. In the end we verify that the correct size has been set.
 IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, NavigateAfterResize) {
   const gfx::Size nxt_size = gfx::Size(100, 200);
-  const std::string embedder_code =
-      StringPrintf("SetSize(%d, %d);", nxt_size.width(), nxt_size.height());
+  const std::string embedder_code = base::StringPrintf(
+      "SetSize(%d, %d);", nxt_size.width(), nxt_size.height());
   const char kEmbedderURL[] = "files/browser_plugin_embedder.html";
   StartBrowserPluginTest(kEmbedderURL, kHTMLForGuest, true, embedder_code);
 
@@ -626,7 +626,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, Renavigate) {
 
     ExecuteSyncJSFunction(
         rvh,
-        StringPrintf("SetSrc('%s');", GetHTMLForGuestWithTitle("P2").c_str()));
+        base::StringPrintf(
+            "SetSrc('%s');", GetHTMLForGuestWithTitle("P2").c_str()));
 
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
@@ -640,7 +641,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, Renavigate) {
 
     ExecuteSyncJSFunction(
         rvh,
-        StringPrintf("SetSrc('%s');", GetHTMLForGuestWithTitle("P3").c_str()));
+        base::StringPrintf(
+            "SetSrc('%s');", GetHTMLForGuestWithTitle("P3").c_str()));
 
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
@@ -719,7 +721,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, ReloadEmbedder) {
     content::TitleWatcher title_watcher(test_embedder()->web_contents(),
                                         expected_title);
 
-    ExecuteSyncJSFunction(rvh, StringPrintf("SetTitle('%s');", "modified"));
+    ExecuteSyncJSFunction(rvh,
+                          base::StringPrintf("SetTitle('%s');", "modified"));
 
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
@@ -738,7 +741,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, ReloadEmbedder) {
 
     ExecuteSyncJSFunction(
         test_embedder()->web_contents()->GetRenderViewHost(),
-        StringPrintf("SetSrc('%s');", kHTMLForGuest));
+        base::StringPrintf("SetSrc('%s');", kHTMLForGuest));
     test_guest_manager()->WaitForGuestAdded();
 
     const TestBrowserPluginGuestManager::GuestInstanceMap& instance_map =
@@ -784,7 +787,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, BackAfterTerminateGuest) {
 
     ExecuteSyncJSFunction(
         rvh,
-        StringPrintf("SetSrc('%s');", GetHTMLForGuestWithTitle("P2").c_str()));
+        base::StringPrintf(
+            "SetSrc('%s');", GetHTMLForGuestWithTitle("P2").c_str()));
 
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
@@ -821,7 +825,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadStart) {
   // Renavigate the guest to |kHTMLForGuest|.
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       test_embedder()->web_contents()->GetRenderViewHost());
-  ExecuteSyncJSFunction(rvh, StringPrintf("SetSrc('%s');", kHTMLForGuest));
+  ExecuteSyncJSFunction(rvh,
+                        base::StringPrintf("SetSrc('%s');", kHTMLForGuest));
 
   string16 actual_title = title_watcher.WaitAndGetTitle();
   EXPECT_EQ(expected_title, actual_title);
@@ -840,7 +845,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadAbort) {
         test_embedder()->web_contents()->GetRenderViewHost());
     GURL test_url = test_server()->GetURL("close-socket");
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
+        rvh, base::StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
   }
@@ -854,7 +859,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadAbort) {
         test_embedder()->web_contents()->GetRenderViewHost());
     GURL test_url("chrome://newtab");
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
+        rvh, base::StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
   }
@@ -868,7 +873,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadAbort) {
         test_embedder()->web_contents()->GetRenderViewHost());
     GURL test_url("file://foo");
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
+        rvh, base::StringPrintf("SetSrc('%s');", test_url.spec().c_str()));
     string16 actual_title = title_watcher.WaitAndGetTitle();
     EXPECT_EQ(expected_title, actual_title);
   }
@@ -888,7 +893,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadRedirect) {
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       test_embedder()->web_contents()->GetRenderViewHost());
   ExecuteSyncJSFunction(
-      rvh, StringPrintf("SetSrc('%s');", redirect_url.spec().c_str()));
+      rvh, base::StringPrintf("SetSrc('%s');", redirect_url.spec().c_str()));
 
   string16 actual_title = title_watcher.WaitAndGetTitle();
   EXPECT_EQ(expected_title, actual_title);
@@ -983,7 +988,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, PostMessage) {
     // By the time we get here 'contentWindow' should be ready because the
     // guest has completed loading.
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("PostMessage('%s, false');", kTesting));
+        rvh, base::StringPrintf("PostMessage('%s, false');", kTesting));
 
     // The title will be updated to "main guest" at the last stage of the
     // process described above.
@@ -1009,7 +1014,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, DISABLED_PostMessageToIFrame) {
                                         expected_title);
 
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("PostMessage('%s, false');", kTesting));
+        rvh, base::StringPrintf("PostMessage('%s, false');", kTesting));
 
     // The title will be updated to "main guest" at the last stage of the
     // process described above.
@@ -1026,7 +1031,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, DISABLED_PostMessageToIFrame) {
         "files/browser_plugin_post_message_guest.html");
     ExecuteSyncJSFunction(
         guest_rvh,
-        StringPrintf("CreateChildFrame('%s');", test_url.spec().c_str()));
+        base::StringPrintf(
+            "CreateChildFrame('%s');", test_url.spec().c_str()));
 
     string16 actual_title = ready_watcher.WaitAndGetTitle();
     EXPECT_EQ(ASCIIToUTF16("ready"), actual_title);
@@ -1034,7 +1040,7 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, DISABLED_PostMessageToIFrame) {
     content::TitleWatcher iframe_watcher(test_embedder()->web_contents(),
                                         ASCIIToUTF16("iframe"));
     ExecuteSyncJSFunction(
-        rvh, StringPrintf("PostMessage('%s', true);", kTesting));
+        rvh, base::StringPrintf("PostMessage('%s', true);", kTesting));
 
     // The title will be updated to "iframe" at the last stage of the
     // process described above.
@@ -1053,7 +1059,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadStop) {
   // Renavigate the guest to |kHTMLForGuest|.
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       test_embedder()->web_contents()->GetRenderViewHost());
-  ExecuteSyncJSFunction(rvh, StringPrintf("SetSrc('%s');", kHTMLForGuest));
+  ExecuteSyncJSFunction(rvh,
+                        base::StringPrintf("SetSrc('%s');", kHTMLForGuest));
 
   string16 actual_title = title_watcher.WaitAndGetTitle();
   EXPECT_EQ(expected_title, actual_title);
@@ -1064,13 +1071,14 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, LoadCommit) {
   StartBrowserPluginTest(kEmbedderURL, "about:blank", true, "");
 
   const string16 expected_title = ASCIIToUTF16(
-      StringPrintf("loadCommit:%s", kHTMLForGuest));
+      base::StringPrintf("loadCommit:%s", kHTMLForGuest));
   content::TitleWatcher title_watcher(
       test_embedder()->web_contents(), expected_title);
   // Renavigate the guest to |kHTMLForGuest|.
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       test_embedder()->web_contents()->GetRenderViewHost());
-  ExecuteSyncJSFunction(rvh, StringPrintf("SetSrc('%s');", kHTMLForGuest));
+  ExecuteSyncJSFunction(rvh,
+                        base::StringPrintf("SetSrc('%s');", kHTMLForGuest));
 
   string16 actual_title = title_watcher.WaitAndGetTitle();
   EXPECT_EQ(expected_title, actual_title);
@@ -1259,7 +1267,8 @@ IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, AutoSizeAfterNavigation) {
 // Test for regression http://crbug.com/162961.
 IN_PROC_BROWSER_TEST_F(BrowserPluginHostTest, GetRenderViewHostAtPositionTest) {
   const char kEmbedderURL[] = "files/browser_plugin_embedder.html";
-  const std::string embedder_code = StringPrintf("SetSize(%d, %d);", 100, 100);
+  const std::string embedder_code =
+      base::StringPrintf("SetSize(%d, %d);", 100, 100);
   StartBrowserPluginTest(kEmbedderURL, kHTMLForGuestWithSize, true,
                          embedder_code);
   // Check for render view host at position (150, 150) that is outside the
diff --git a/content/browser/devtools/devtools_http_handler_impl.cc b/content/browser/devtools/devtools_http_handler_impl.cc
index 5f705cd..fa0ca6d 100644
--- a/content/browser/devtools/devtools_http_handler_impl.cc
+++ b/content/browser/devtools/devtools_http_handler_impl.cc
@@ -704,7 +704,7 @@ void DevToolsHttpHandlerImpl::SendJson(int connection_id,
   std::string response;
   std::string mime_type = "application/json; charset=UTF-8";
 
-  response = StringPrintf("%s%s", json_value.c_str(), message.c_str());
+  response = base::StringPrintf("%s%s", json_value.c_str(), message.c_str());
 
   thread_->message_loop()->PostTask(
       FROM_HERE,
diff --git a/content/browser/download/download_browsertest.cc b/content/browser/download/download_browsertest.cc
index a62cd89..b602497 100644
--- a/content/browser/download/download_browsertest.cc
+++ b/content/browser/download/download_browsertest.cc
@@ -957,7 +957,7 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest, ResumeInterruptedDownload) {
   ASSERT_TRUE(test_server()->Start());
 
   GURL url = test_server()->GetURL(
-      StringPrintf("rangereset?size=%d&rst_boundary=%d",
+      base::StringPrintf("rangereset?size=%d&rst_boundary=%d",
                    GetSafeBufferChunk() * 3, GetSafeBufferChunk()));
 
   DownloadItem* download(StartDownloadAndReturnItem(url));
@@ -1018,7 +1018,7 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest, ResumeInterruptedDownloadNoRange) {
 
   // Auto-restart if server doesn't handle ranges.
   GURL url = test_server()->GetURL(
-      StringPrintf(
+      base::StringPrintf(
           // First download hits an RST, rest don't, no ranges.
           "rangereset?size=%d&rst_boundary=%d&"
           "token=NoRange&rst_limit=1&bounce_range",
@@ -1066,7 +1066,7 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest,
   ASSERT_TRUE(test_server()->Start());
 
   GURL url = test_server()->GetURL(
-      StringPrintf(
+      base::StringPrintf(
           // First download hits an RST, rest don't, precondition fail.
           "rangereset?size=%d&rst_boundary=%d&"
           "token=NoRange&rst_limit=1&fail_precondition=2",
@@ -1116,7 +1116,7 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest,
   ASSERT_TRUE(test_server()->Start());
 
   GURL url = test_server()->GetURL(
-      StringPrintf(
+      base::StringPrintf(
           // First download hits an RST, rest don't, no verifiers.
           "rangereset?size=%d&rst_boundary=%d&"
           "token=NoRange&rst_limit=1&no_verifiers",
@@ -1160,7 +1160,7 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest, ResumeWithDeletedFile) {
   ASSERT_TRUE(test_server()->Start());
 
   GURL url = test_server()->GetURL(
-      StringPrintf(
+      base::StringPrintf(
           // First download hits an RST, rest don't
           "rangereset?size=%d&rst_boundary=%d&"
           "token=NoRange&rst_limit=1",
diff --git a/content/browser/download/download_file_impl.cc b/content/browser/download/download_file_impl.cc
index 5ee2187..fb6b095 100644
--- a/content/browser/download/download_file_impl.cc
+++ b/content/browser/download/download_file_impl.cc
@@ -112,7 +112,7 @@ void DownloadFileImpl::RenameAndUniquify(
       file_util::GetUniquePathNumber(new_path, FILE_PATH_LITERAL(""));
   if (uniquifier > 0) {
     new_path = new_path.InsertBeforeExtensionASCII(
-        StringPrintf(" (%d)", uniquifier));
+        base::StringPrintf(" (%d)", uniquifier));
   }
 
   DownloadInterruptReason reason = file_.Rename(new_path);
diff --git a/content/browser/download/download_manager_impl.cc b/content/browser/download/download_manager_impl.cc
index c9fe58c..752f16d 100644
--- a/content/browser/download/download_manager_impl.cc
+++ b/content/browser/download/download_manager_impl.cc
@@ -95,7 +95,7 @@ void BeginDownload(scoped_ptr<DownloadUrlParameters> params,
   if (params->offset() > 0) {
     request->SetExtraRequestHeaderByName(
         "Range",
-        StringPrintf("bytes=%" PRId64 "-", params->offset()),
+        base::StringPrintf("bytes=%" PRId64 "-", params->offset()),
         true);
 
     if (has_last_modified) {
diff --git a/content/browser/download/save_package.cc b/content/browser/download/save_package.cc
index 45195e0..c5171ee 100644
--- a/content/browser/download/save_package.cc
+++ b/content/browser/download/save_package.cc
@@ -515,7 +515,7 @@ bool SavePackage::GenerateFileName(const std::string& disposition,
     } else {
       for (int i = ordinal_number; i < kMaxFileOrdinalNumber; ++i) {
         base::FilePath::StringType new_name = base_file_name +
-            StringPrintf(FILE_PATH_LITERAL("(%d)"), i) + file_name_ext;
+            base::StringPrintf(FILE_PATH_LITERAL("(%d)"), i) + file_name_ext;
         if (file_name_set_.find(new_name) == file_name_set_.end()) {
           // Resolved name conflict.
           file_name = new_name;
diff --git a/content/browser/geolocation/wifi_data_provider_chromeos_unittest.cc b/content/browser/geolocation/wifi_data_provider_chromeos_unittest.cc
index e6e6404..8fcb6c5 100644
--- a/content/browser/geolocation/wifi_data_provider_chromeos_unittest.cc
+++ b/content/browser/geolocation/wifi_data_provider_chromeos_unittest.cc
@@ -46,8 +46,8 @@ class GeolocationChromeOsWifiDataProviderTest : public testing::Test {
         std::string mac_address =
             base::StringPrintf("%02X:%02X:%02X:%02X:%02X:%02X",
                                i, j, 3, 4, 5, 6);
-        std::string channel = StringPrintf("%d", i * 10 + j);
-        std::string strength = StringPrintf("%d", i * 100 + j);
+        std::string channel = base::StringPrintf("%d", i * 10 + j);
+        std::string strength = base::StringPrintf("%d", i * 100 + j);
         properties.SetStringWithoutPathExpansion(
             shill::kGeoMacAddressProperty, mac_address);
         properties.SetStringWithoutPathExpansion(
diff --git a/content/browser/renderer_host/java/java_bound_object.cc b/content/browser/renderer_host/java/java_bound_object.cc
index 5d50948..4a239a5 100644
--- a/content/browser/renderer_host/java/java_bound_object.cc
+++ b/content/browser/renderer_host/java/java_bound_object.cc
@@ -271,9 +271,9 @@ jvalue CoerceJavaScriptNumberToJavaValue(const NPVariant& variant,
       result.l = coerce_to_string ?
           ConvertUTF8ToJavaString(
               AttachCurrentThread(),
-              is_double ? StringPrintf("%.6lg", NPVARIANT_TO_DOUBLE(variant)) :
-                          base::Int64ToString(NPVARIANT_TO_INT32(variant))).
-                              Release() :
+              is_double ?
+                  base::StringPrintf("%.6lg", NPVARIANT_TO_DOUBLE(variant)) :
+                  base::Int64ToString(NPVARIANT_TO_INT32(variant))).Release() :
           NULL;
       break;
     case JavaType::TypeBoolean:
diff --git a/content/browser/renderer_host/java/java_bridge_channel_host.cc b/content/browser/renderer_host/java/java_bridge_channel_host.cc
index 20039e8..5b40ab4 100644
--- a/content/browser/renderer_host/java/java_bridge_channel_host.cc
+++ b/content/browser/renderer_host/java/java_bridge_channel_host.cc
@@ -39,7 +39,7 @@ JavaBridgeChannelHost::~JavaBridgeChannelHost() {
 JavaBridgeChannelHost* JavaBridgeChannelHost::GetJavaBridgeChannelHost(
     int renderer_id,
     base::MessageLoopProxy* ipc_message_loop) {
-  std::string channel_name(StringPrintf("r%d.javabridge", renderer_id));
+  std::string channel_name(base::StringPrintf("r%d.javabridge", renderer_id));
   // There's no need for a shutdown event here. If the browser is terminated
   // while the JavaBridgeChannelHost is blocked on a synchronous IPC call, the
   // renderer's shutdown event will cause the underlying channel to shut down,
diff --git a/content/browser/renderer_host/media/video_capture_host_unittest.cc b/content/browser/renderer_host/media/video_capture_host_unittest.cc
index 89bdf36..4c6334f 100644
--- a/content/browser/renderer_host/media/video_capture_host_unittest.cc
+++ b/content/browser/renderer_host/media/video_capture_host_unittest.cc
@@ -53,8 +53,8 @@ class DumpVideo {
  public:
   DumpVideo() : expected_size_(0) {}
   void StartDump(int width, int height) {
-    base::FilePath file_name = base::FilePath(
-        StringPrintf(FILE_PATH_LITERAL("dump_w%d_h%d.yuv"), width, height));
+    base::FilePath file_name = base::FilePath(base::StringPrintf(
+        FILE_PATH_LITERAL("dump_w%d_h%d.yuv"), width, height));
     file_.reset(file_util::OpenFile(file_name, "wb"));
     expected_size_ = width * height * 3 / 2;
   }
diff --git a/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc b/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
index 8bb0e35..b53eadd 100644
--- a/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
+++ b/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
@@ -490,8 +490,9 @@ TEST_F(WebContentsVideoCaptureDeviceTest, GoesThroughAllTheMotions) {
 
   bool use_video_frames = false;
   for (int i = 0; i < 4; i++, use_video_frames = !use_video_frames) {
-    SCOPED_TRACE(StringPrintf("Using %s copy path, iteration #%d",
-                              use_video_frames ? "VideoFrame" : "SkBitmap", i));
+    SCOPED_TRACE(base::StringPrintf(
+        "Using %s copy path, iteration #%d",
+        use_video_frames ? "VideoFrame" : "SkBitmap", i));
     source()->SetCanCopyToVideoFrame(use_video_frames);
     source()->SetSolidColor(SK_ColorRED);
     ASSERT_NO_FATAL_FAILURE(source()->WaitForNextBackingStoreCopy());
diff --git a/content/browser/web_contents/navigation_controller_impl_unittest.cc b/content/browser/web_contents/navigation_controller_impl_unittest.cc
index 22b55a8..1d698b3 100644
--- a/content/browser/web_contents/navigation_controller_impl_unittest.cc
+++ b/content/browser/web_contents/navigation_controller_impl_unittest.cc
@@ -1985,7 +1985,7 @@ TEST_F(NavigationControllerTest, EnforceMaxNavigationCount) {
   int url_index;
   // Load up to the max count, all entries should be there.
   for (url_index = 0; url_index < kMaxEntryCount; url_index++) {
-    GURL url(StringPrintf("http://www.a.com/%d", url_index));
+    GURL url(base::StringPrintf("http://www.a.com/%d", url_index));
     controller.LoadURL(
         url, Referrer(), PAGE_TRANSITION_TYPED, std::string());
     test_rvh()->SendNavigate(url_index, url);
@@ -1997,7 +1997,7 @@ TEST_F(NavigationControllerTest, EnforceMaxNavigationCount) {
   PrunedListener listener(&controller);
 
   // Navigate some more.
-  GURL url(StringPrintf("http://www.a.com/%d", url_index));
+  GURL url(base::StringPrintf("http://www.a.com/%d", url_index));
   controller.LoadURL(
       url, Referrer(), PAGE_TRANSITION_TYPED, std::string());
   test_rvh()->SendNavigate(url_index, url);
@@ -2015,7 +2015,7 @@ TEST_F(NavigationControllerTest, EnforceMaxNavigationCount) {
 
   // More navigations.
   for (int i = 0; i < 3; i++) {
-    url = GURL(StringPrintf("http:////www.a.com/%d", url_index));
+    url = GURL(base::StringPrintf("http:////www.a.com/%d", url_index));
     controller.LoadURL(
         url, Referrer(), PAGE_TRANSITION_TYPED, std::string());
     test_rvh()->SendNavigate(url_index, url);
diff --git a/content/browser/worker_host/test/worker_browsertest.cc b/content/browser/worker_host/test/worker_browsertest.cc
index 0c335b6..6ef70b6 100644
--- a/content/browser/worker_host/test/worker_browsertest.cc
+++ b/content/browser/worker_host/test/worker_browsertest.cc
@@ -351,7 +351,7 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, DISABLED_LimitPerPage) {
 IN_PROC_BROWSER_TEST_F(WorkerTest, LimitPerPage) {
 #endif
   int max_workers_per_tab = WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate;
-  std::string query = StringPrintf("?count=%d", max_workers_per_tab + 1);
+  std::string query = base::StringPrintf("?count=%d", max_workers_per_tab + 1);
 
   GURL url = GetTestURL("many_shared_workers.html", query);
   NavigateToURL(shell(), url);
@@ -374,15 +374,17 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, LimitTotal) {
   int max_workers_per_tab = WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate;
   int total_workers = WorkerServiceImpl::kMaxWorkersWhenSeparate;
 
-  std::string query = StringPrintf("?count=%d", max_workers_per_tab);
+  std::string query = base::StringPrintf("?count=%d", max_workers_per_tab);
   GURL url = GetTestURL("many_shared_workers.html", query);
-  NavigateToURL(shell(), GURL(url.spec() + StringPrintf("&client_id=0")));
+  NavigateToURL(shell(),
+                GURL(url.spec() + base::StringPrintf("&client_id=0")));
 
   // Adding 1 so that we cause some workers to be queued.
   int tab_count = (total_workers / max_workers_per_tab) + 1;
   for (int i = 1; i < tab_count; ++i) {
     NavigateToURL(
-        CreateBrowser(), GURL(url.spec() + StringPrintf("&client_id=%d", i)));
+        CreateBrowser(),
+        GURL(url.spec() + base::StringPrintf("&client_id=%d", i)));
   }
 
   // Check that we didn't create more than the max number of workers.
@@ -406,7 +408,7 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, QueuedSharedWorkerShutdown) {
   // Tests to make sure that queued shared workers are started up when shared
   // workers shut down.
   int max_workers_per_tab = WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate;
-  std::string query = StringPrintf("?count=%d", max_workers_per_tab);
+  std::string query = base::StringPrintf("?count=%d", max_workers_per_tab);
   RunTest("queued_shared_worker_shutdown.html", query);
   ASSERT_TRUE(WaitForWorkerProcessCount(max_workers_per_tab));
 }
@@ -418,7 +420,7 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, DISABLED_MultipleTabsQueuedSharedWorker) {
   // Tests to make sure that only one instance of queued shared workers are
   // started up even when those instances are on multiple tabs.
   int max_workers_per_tab = WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate;
-  std::string query = StringPrintf("?count=%d", max_workers_per_tab + 1);
+  std::string query = base::StringPrintf("?count=%d", max_workers_per_tab + 1);
   GURL url = GetTestURL("many_shared_workers.html", query);
   NavigateToURL(shell(), url);
   ASSERT_TRUE(WaitForWorkerProcessCount(max_workers_per_tab));
@@ -441,7 +443,7 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, DISABLED_QueuedSharedWorkerStartedFromOtherTa
   // Tests to make sure that queued shared workers are started up when
   // an instance is launched from another tab.
   int max_workers_per_tab = WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate;
-  std::string query = StringPrintf("?count=%d", max_workers_per_tab + 1);
+  std::string query = base::StringPrintf("?count=%d", max_workers_per_tab + 1);
   GURL url = GetTestURL("many_shared_workers.html", query);
   NavigateToURL(shell(), url);
   ASSERT_TRUE(WaitForWorkerProcessCount(max_workers_per_tab));
@@ -449,7 +451,7 @@ IN_PROC_BROWSER_TEST_F(WorkerTest, DISABLED_QueuedSharedWorkerStartedFromOtherTa
   // First window has hit its limit. Now launch second window which creates
   // the same worker that was queued in the first window, to ensure it gets
   // connected to the first window too.
-  query = StringPrintf("?id=%d", max_workers_per_tab);
+  query = base::StringPrintf("?id=%d", max_workers_per_tab);
   url = GetTestURL("single_shared_worker.html", query);
   NavigateToURL(CreateBrowser(), url);
 
diff --git a/content/common/content_param_traits.cc b/content/common/content_param_traits.cc
index f080331..63f8468 100644
--- a/content/common/content_param_traits.cc
+++ b/content/common/content_param_traits.cc
@@ -129,7 +129,8 @@ bool ParamTraits<NPVariant_Param>::Read(const Message* m,
 }
 
 void ParamTraits<NPVariant_Param>::Log(const param_type& p, std::string* l) {
-  l->append(StringPrintf("NPVariant_Param(%d, ", static_cast<int>(p.type)));
+  l->append(
+      base::StringPrintf("NPVariant_Param(%d, ", static_cast<int>(p.type)));
   if (p.type == content::NPVARIANT_PARAM_BOOL) {
     LogParam(p.bool_value, l);
   } else if (p.type == content::NPVARIANT_PARAM_INT) {
diff --git a/content/gpu/gpu_info_collector_win.cc b/content/gpu/gpu_info_collector_win.cc
index f1d5516..54ac7c1 100644
--- a/content/gpu/gpu_info_collector_win.cc
+++ b/content/gpu/gpu_info_collector_win.cc
@@ -498,13 +498,13 @@ bool CollectContextGraphicsInfo(content::GPUInfo* gpu_info) {
                         &pixel_shader_minor_version)) {
     gpu_info->can_lose_context = direct3d_version == "9";
     gpu_info->vertex_shader_version =
-        StringPrintf("%d.%d",
-                     vertex_shader_major_version,
-                     vertex_shader_minor_version);
+        base::StringPrintf("%d.%d",
+                           vertex_shader_major_version,
+                           vertex_shader_minor_version);
     gpu_info->pixel_shader_version =
-        StringPrintf("%d.%d",
-                     pixel_shader_major_version,
-                     pixel_shader_minor_version);
+        base::StringPrintf("%d.%d",
+                           pixel_shader_major_version,
+                           pixel_shader_minor_version);
 
     // DirectX diagnostics are collected asynchronously because it takes a
     // couple of seconds. Do not mark gpu_info as complete until that is done.
diff --git a/content/plugin/plugin_channel.cc b/content/plugin/plugin_channel.cc
index 79754fa..8569a3d 100644
--- a/content/plugin/plugin_channel.cc
+++ b/content/plugin/plugin_channel.cc
@@ -143,7 +143,7 @@ class PluginChannel::MessageFilter : public IPC::ChannelProxy::MessageFilter {
 PluginChannel* PluginChannel::GetPluginChannel(
     int renderer_id, base::MessageLoopProxy* ipc_message_loop) {
   // Map renderer ID to a (single) channel to that process.
-  std::string channel_key = StringPrintf(
+  std::string channel_key = base::StringPrintf(
       "%d.r%d", base::GetCurrentProcId(), renderer_id);
 
   PluginChannel* channel =
diff --git a/content/ppapi_plugin/ppapi_thread.cc b/content/ppapi_plugin/ppapi_thread.cc
index bed78b8..373e7cce 100644
--- a/content/ppapi_plugin/ppapi_thread.cc
+++ b/content/ppapi_plugin/ppapi_thread.cc
@@ -410,7 +410,8 @@ bool PpapiThread::SetupRendererChannel(base::ProcessId renderer_pid,
   DCHECK(is_broker_ == (connect_instance_func_ != NULL));
   IPC::ChannelHandle plugin_handle;
   plugin_handle.name = IPC::Channel::GenerateVerifiedChannelID(
-      StringPrintf("%d.r%d", base::GetCurrentProcId(), renderer_child_id));
+      base::StringPrintf(
+          "%d.r%d", base::GetCurrentProcId(), renderer_child_id));
 
   ppapi::proxy::ProxyChannel* dispatcher = NULL;
   bool init_result = false;
diff --git a/content/public/test/render_widget_test.cc b/content/public/test/render_widget_test.cc
index 260776d..8d8e897 100644
--- a/content/public/test/render_widget_test.cc
+++ b/content/public/test/render_widget_test.cc
@@ -74,7 +74,7 @@ void RenderWidgetTest::ResizeAndPaint(const gfx::Size& page_size,
 void RenderWidgetTest::TestResizeAndPaint() {
   // Hello World message is only visible if the view size is at least
   // kTextPositionX x kTextPositionY
-  LoadHTML(StringPrintf(
+  LoadHTML(base::StringPrintf(
       "<html><body><div style='position: absolute; top: %d; left: "
       "%d; background-color: red;'>Hello World</div></body></html>",
       kTextPositionY, kTextPositionX).c_str());
diff --git a/content/renderer/browser_plugin/browser_plugin_browsertest.cc b/content/renderer/browser_plugin/browser_plugin_browsertest.cc
index 723ef18..e8f38ee 100644
--- a/content/renderer/browser_plugin/browser_plugin_browsertest.cc
+++ b/content/renderer/browser_plugin/browser_plugin_browsertest.cc
@@ -47,8 +47,8 @@ const char kHTMLForPartitionedPersistedPluginObject[] =
     "  src='foo' type='%s' partition='persist:someid'>";
 
 std::string GetHTMLForBrowserPluginObject() {
-  return StringPrintf(kHTMLForBrowserPluginObject,
-                      content::kBrowserPluginMimeType);
+  return base::StringPrintf(kHTMLForBrowserPluginObject,
+                            content::kBrowserPluginMimeType);
 }
 
 }  // namespace
@@ -198,8 +198,8 @@ TEST_F(BrowserPluginTest, InitialResize) {
 // parsed on initialization. However, this test does minimal checking of
 // correct behavior.
 TEST_F(BrowserPluginTest, ParseAllAttributes) {
-  std::string html = StringPrintf(kHTMLForBrowserPluginWithAllAttributes,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForBrowserPluginWithAllAttributes,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   bool result;
   bool has_value = ExecuteScriptAndReturnBool(
@@ -448,8 +448,8 @@ TEST_F(BrowserPluginTest, RemovePlugin) {
 // This test verifies that PluginDestroyed messages do not get sent from a
 // BrowserPlugin that has never navigated.
 TEST_F(BrowserPluginTest, RemovePluginBeforeNavigation) {
-  std::string html = StringPrintf(kHTMLForSourcelessPluginObject,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForSourcelessPluginObject,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   EXPECT_FALSE(browser_plugin_manager()->sink().GetUniqueMessageMatching(
       BrowserPluginHostMsg_PluginDestroyed::ID));
@@ -544,15 +544,15 @@ TEST_F(BrowserPluginTest, ReloadMethod) {
 // Verify that the 'partition' attribute on the browser plugin is parsed
 // correctly.
 TEST_F(BrowserPluginTest, PartitionAttribute) {
-  std::string html = StringPrintf(kHTMLForPartitionedPluginObject,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForPartitionedPluginObject,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   std::string partition_value = ExecuteScriptAndReturnString(
       "document.getElementById('browserplugin').partition");
   EXPECT_STREQ("someid", partition_value.c_str());
 
-  html = StringPrintf(kHTMLForPartitionedPersistedPluginObject,
-                      content::kBrowserPluginMimeType);
+  html = base::StringPrintf(kHTMLForPartitionedPersistedPluginObject,
+                            content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   partition_value = ExecuteScriptAndReturnString(
       "document.getElementById('browserplugin').partition");
@@ -571,8 +571,8 @@ TEST_F(BrowserPluginTest, PartitionAttribute) {
       title.c_str());
 
   // Load a browser tag without 'src' defined.
-  html = StringPrintf(kHTMLForSourcelessPluginObject,
-                      content::kBrowserPluginMimeType);
+  html = base::StringPrintf(kHTMLForSourcelessPluginObject,
+                            content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
 
   // Ensure we don't parse just "persist:" string and return exception.
@@ -588,8 +588,8 @@ TEST_F(BrowserPluginTest, PartitionAttribute) {
 // This test verifies that BrowserPlugin enters an error state when the
 // partition attribute is invalid.
 TEST_F(BrowserPluginTest, InvalidPartition) {
-  std::string html = StringPrintf(kHTMLForInvalidPartitionedPluginObject,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForInvalidPartitionedPluginObject,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   // Attempt to navigate with an invalid partition.
   {
@@ -634,8 +634,8 @@ TEST_F(BrowserPluginTest, InvalidPartition) {
 // Test to verify that after the first navigation, the partition attribute
 // cannot be modified.
 TEST_F(BrowserPluginTest, ImmutableAttributesAfterNavigation) {
-  std::string html = StringPrintf(kHTMLForSourcelessPluginObject,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForSourcelessPluginObject,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
 
   ExecuteJavaScript(
@@ -828,8 +828,8 @@ TEST_F(BrowserPluginTest, RemoveBrowserPluginOnExit) {
 }
 
 TEST_F(BrowserPluginTest, AutoSizeAttributes) {
-  std::string html = StringPrintf(kHTMLForSourcelessPluginObject,
-                                  content::kBrowserPluginMimeType);
+  std::string html = base::StringPrintf(kHTMLForSourcelessPluginObject,
+                                        content::kBrowserPluginMimeType);
   LoadHTML(html.c_str());
   const char* kSetAutoSizeParametersAndNavigate =
     "var browserplugin = document.getElementById('browserplugin');"
diff --git a/content/renderer/media/media_stream_impl.cc b/content/renderer/media/media_stream_impl.cc
index e89a9ac..c9a225d 100644
--- a/content/renderer/media/media_stream_impl.cc
+++ b/content/renderer/media/media_stream_impl.cc
@@ -84,9 +84,9 @@ void CreateWebKitSourceVector(
   for (size_t i = 0; i < devices.size(); ++i) {
     const char* track_type =
         (type == WebKit::WebMediaStreamSource::TypeAudio) ? "a" : "v";
-    std::string source_id = StringPrintf("%s%s%u", label.c_str(),
-                                         track_type,
-                                         static_cast<unsigned int>(i));
+    std::string source_id = base::StringPrintf("%s%s%u", label.c_str(),
+                                               track_type,
+                                               static_cast<unsigned int>(i));
     webkit_sources[i].initialize(
           UTF8ToUTF16(source_id),
           type,
diff --git a/content/renderer/media/mock_media_stream_dispatcher.cc b/content/renderer/media/mock_media_stream_dispatcher.cc
index ac8963a..09858c1 100644
--- a/content/renderer/media/mock_media_stream_dispatcher.cc
+++ b/content/renderer/media/mock_media_stream_dispatcher.cc
@@ -26,7 +26,7 @@ void MockMediaStreamDispatcher::GenerateStream(
     const GURL& url) {
   request_id_ = request_id;
 
-  stream_label_ = StringPrintf("%s%d","local_stream",request_id);
+  stream_label_ = base::StringPrintf("%s%d","local_stream",request_id);
   audio_array_.clear();
   video_array_.clear();
 
diff --git a/content/test/layout_browsertest.cc b/content/test/layout_browsertest.cc
index 0140aff..4c34a38 100644
--- a/content/test/layout_browsertest.cc
+++ b/content/test/layout_browsertest.cc
@@ -140,7 +140,7 @@ void InProcessBrowserLayoutTest::RunLayoutTest(
 void InProcessBrowserLayoutTest::RunHttpLayoutTest(
     const std::string& test_case_file_name) {
   DCHECK(test_http_server_.get());
-  GURL url(StringPrintf(
+  GURL url(base::StringPrintf(
       "http://127.0.0.1:%d/%s/%s", port_, test_case_dir_.MaybeAsASCII().c_str(),
       test_case_file_name.c_str()));
   RunLayoutTestInternal(test_case_file_name, url);
@@ -205,9 +205,9 @@ std::string InProcessBrowserLayoutTest::SaveResults(const std::string& expected,
   EXPECT_NE(-1, file_util::WriteFile(actual_filename,
                                      actual.c_str(),
                                      actual.size()));
-  return StringPrintf("Wrote %"PRFilePath" %"PRFilePath,
-                      expected_filename.value().c_str(),
-                      actual_filename.value().c_str());
+  return base::StringPrintf("Wrote %"PRFilePath" %"PRFilePath,
+                            expected_filename.value().c_str(),
+                            actual_filename.value().c_str());
 }
 
 }  // namespace content
diff --git a/courgette/adjustment_method.cc b/courgette/adjustment_method.cc
index 53745d7..ac0f0a1 100644
--- a/courgette/adjustment_method.cc
+++ b/courgette/adjustment_method.cc
@@ -169,7 +169,7 @@ static std::string ToString(Node* node) {
     prefix.pop_back();
   }
 
-  s += StringPrintf("%u", node->count_);
+  s += base::StringPrintf("%u", node->count_);
   s += " @";
   s += base::Uint64ToString(node->edges_in_frequency_order.size());
   s += "}";
diff --git a/courgette/memory_monitor.cc b/courgette/memory_monitor.cc
index dba8a88..89f82fb 100644
--- a/courgette/memory_monitor.cc
+++ b/courgette/memory_monitor.cc
@@ -16,17 +16,17 @@ struct H {
     int i = 0;
     for (M::iterator p = m_.begin(); p != m_.end(); ++p, ++i) {
       size_t s = p->first;
-      LOG(INFO) << StringPrintf("%3d %8u: %8u %8u %8u %8u", i, s,
+      LOG(INFO) << base::StringPrintf("%3d %8u: %8u %8u %8u %8u", i, s,
              m_[s], c_[s], h_[s], h_[s] * s);
     }
     LOG(INFO) << "Peak " << fmt(high_);
   }
 
   std::string fmt(size_t s) {
-    if (s > 1000000000) return StringPrintf("%.3gG", s/(1000000000.0));
-    if (s > 1000000) return StringPrintf("%.3gM", s/(1000000.));
-    if (s > 9999) return StringPrintf("%.3gk", s/(1000.));
-    return StringPrintf("%d", (int)s);
+    if (s > 1000000000) return base::StringPrintf("%.3gG", s/(1000000000.0));
+    if (s > 1000000) return base::StringPrintf("%.3gM", s/(1000000.));
+    if (s > 9999) return base::StringPrintf("%.3gk", s/(1000.));
+    return base::StringPrintf("%d", (int)s);
   }
 
   void tick(size_t w, char sign) {
diff --git a/crypto/nss_util.cc b/crypto/nss_util.cc
index a53fa40..0d4b1141 100644
--- a/crypto/nss_util.cc
+++ b/crypto/nss_util.cc
@@ -73,7 +73,7 @@ std::string GetNSSErrorMessage() {
     PRInt32 copied = PR_GetErrorText(error_text.get());
     result = std::string(error_text.get(), copied);
   } else {
-    result = StringPrintf("NSS error code: %d", PR_GetError());
+    result = base::StringPrintf("NSS error code: %d", PR_GetError());
   }
   return result;
 }
@@ -482,7 +482,7 @@ class NSSInitSingleton {
         // Initialize with a persistent database (likely, ~/.pki/nssdb).
         // Use "sql:" which can be shared by multiple processes safely.
         std::string nss_config_dir =
-            StringPrintf("sql:%s", database_dir.value().c_str());
+            base::StringPrintf("sql:%s", database_dir.value().c_str());
 #if defined(OS_CHROMEOS)
         status = NSS_Init(nss_config_dir.c_str());
 #else
@@ -586,7 +586,7 @@ class NSSInitSingleton {
   SECMODModule* LoadModule(const char* name,
                            const char* library_path,
                            const char* params) {
-    std::string modparams = StringPrintf(
+    std::string modparams = base::StringPrintf(
         "name=\"%s\" library=\"%s\" %s",
         name, library_path, params ? params : "");
 
@@ -608,8 +608,8 @@ class NSSInitSingleton {
   static PK11SlotInfo* OpenUserDB(const base::FilePath& path,
                                   const char* description) {
     const std::string modspec =
-        StringPrintf("configDir='sql:%s' tokenDescription='%s'",
-                     path.value().c_str(), description);
+        base::StringPrintf("configDir='sql:%s' tokenDescription='%s'",
+                           path.value().c_str(), description);
     PK11SlotInfo* db_slot = SECMOD_OpenUserDB(modspec.c_str());
     if (db_slot) {
       if (PK11_NeedUserInit(db_slot))
diff --git a/dbus/dbus_statistics.cc b/dbus/dbus_statistics.cc
index 8368c4c..eeb2f0ac 100644
--- a/dbus/dbus_statistics.cc
+++ b/dbus/dbus_statistics.cc
@@ -220,34 +220,35 @@ std::string GetAsString(ShowInString show, FormatString format) {
       if (show >= SHOW_METHOD)
         line += "." + stat->method;
     }
-    line += StringPrintf(":");
+    line += base::StringPrintf(":");
     if (sent_blocking) {
-      line += StringPrintf(" Sent (BLOCKING):");
+      line += base::StringPrintf(" Sent (BLOCKING):");
       if (format == FORMAT_TOTALS)
-        line += StringPrintf(" %d", sent_blocking);
+        line += base::StringPrintf(" %d", sent_blocking);
       else if (format == FORMAT_PER_MINUTE)
-        line += StringPrintf(" %d/min", sent_blocking / dminutes);
+        line += base::StringPrintf(" %d/min", sent_blocking / dminutes);
       else if (format == FORMAT_ALL)
-        line += StringPrintf(" %d (%d/min)",
-                             sent_blocking, sent_blocking / dminutes);
+        line += base::StringPrintf(" %d (%d/min)",
+                                   sent_blocking, sent_blocking / dminutes);
     }
     if (sent) {
-      line += StringPrintf(" Sent:");
+      line += base::StringPrintf(" Sent:");
       if (format == FORMAT_TOTALS)
-        line += StringPrintf(" %d", sent);
+        line += base::StringPrintf(" %d", sent);
       else if (format == FORMAT_PER_MINUTE)
-        line += StringPrintf(" %d/min", sent / dminutes);
+        line += base::StringPrintf(" %d/min", sent / dminutes);
       else if (format == FORMAT_ALL)
-        line += StringPrintf(" %d (%d/min)", sent, sent / dminutes);
+        line += base::StringPrintf(" %d (%d/min)", sent, sent / dminutes);
     }
     if (received) {
-      line += StringPrintf(" Received:");
+      line += base::StringPrintf(" Received:");
       if (format == FORMAT_TOTALS)
-        line += StringPrintf(" %d", received);
+        line += base::StringPrintf(" %d", received);
       else if (format == FORMAT_PER_MINUTE)
-        line += StringPrintf(" %d/min", received / dminutes);
+        line += base::StringPrintf(" %d/min", received / dminutes);
       else if (format == FORMAT_ALL)
-        line += StringPrintf(" %d (%d/min)", received, received / dminutes);
+        line += base::StringPrintf(
+            " %d (%d/min)", received, received / dminutes);
     }
     result += line + "\n";
     sent = 0;
diff --git a/google_apis/gaia/gaia_auth_fetcher.cc b/google_apis/gaia/gaia_auth_fetcher.cc
index c40a3be..822fc98 100644
--- a/google_apis/gaia/gaia_auth_fetcher.cc
+++ b/google_apis/gaia/gaia_auth_fetcher.cc
@@ -306,9 +306,9 @@ std::string GaiaAuthFetcher::MakeGetAuthCodeBody() {
       GaiaUrls::GetInstance()->oauth1_login_scope(), true);
   std::string encoded_client_id = net::EscapeUrlEncodedData(
       GaiaUrls::GetInstance()->oauth2_chrome_client_id(), true);
-  return StringPrintf(kClientLoginToOAuth2BodyFormat,
-                      encoded_scope.c_str(),
-                      encoded_client_id.c_str());
+  return base::StringPrintf(kClientLoginToOAuth2BodyFormat,
+                            encoded_scope.c_str(),
+                            encoded_client_id.c_str());
 }
 
 // static
@@ -321,11 +321,11 @@ std::string GaiaAuthFetcher::MakeGetTokenPairBody(
   std::string encoded_client_secret = net::EscapeUrlEncodedData(
       GaiaUrls::GetInstance()->oauth2_chrome_client_secret(), true);
   std::string encoded_auth_code = net::EscapeUrlEncodedData(auth_code, true);
-  return StringPrintf(kOAuth2CodeToTokenPairBodyFormat,
-                      encoded_scope.c_str(),
-                      encoded_client_id.c_str(),
-                      encoded_client_secret.c_str(),
-                      encoded_auth_code.c_str());
+  return base::StringPrintf(kOAuth2CodeToTokenPairBodyFormat,
+                            encoded_scope.c_str(),
+                            encoded_client_id.c_str(),
+                            encoded_client_secret.c_str(),
+                            encoded_auth_code.c_str());
 }
 
 // static
@@ -352,7 +352,7 @@ std::string GaiaAuthFetcher::MakeMergeSessionBody(
 // static
 std::string GaiaAuthFetcher::MakeGetAuthCodeHeader(
     const std::string& auth_token) {
-  return StringPrintf(kAuthHeaderFormat, auth_token.c_str());
+  return base::StringPrintf(kAuthHeaderFormat, auth_token.c_str());
 }
 
 // Helper method that extracts tokens from a successful reply.
@@ -450,9 +450,9 @@ std::string GaiaAuthFetcher::MakeOAuthLoginBody(const std::string& service,
                                                 const std::string& source) {
   std::string encoded_service = net::EscapeUrlEncodedData(service, true);
   std::string encoded_source = net::EscapeUrlEncodedData(source, true);
-  return StringPrintf(kOAuthLoginFormat,
-                      encoded_service.c_str(),
-                      encoded_source.c_str());
+  return base::StringPrintf(kOAuthLoginFormat,
+                            encoded_service.c_str(),
+                            encoded_source.c_str());
 }
 
 // static
diff --git a/google_apis/gaia/oauth2_access_token_fetcher.cc b/google_apis/gaia/oauth2_access_token_fetcher.cc
index 0cd4456..edefa7e 100644
--- a/google_apis/gaia/oauth2_access_token_fetcher.cc
+++ b/google_apis/gaia/oauth2_access_token_fetcher.cc
@@ -188,14 +188,14 @@ std::string OAuth2AccessTokenFetcher::MakeGetAccessTokenBody(
   std::string enc_refresh_token =
       net::EscapeUrlEncodedData(refresh_token, true);
   if (scopes.empty()) {
-    return StringPrintf(
+    return base::StringPrintf(
         kGetAccessTokenBodyFormat,
         enc_client_id.c_str(),
         enc_client_secret.c_str(),
         enc_refresh_token.c_str());
   } else {
     std::string scopes_string = JoinString(scopes, ' ');
-    return StringPrintf(
+    return base::StringPrintf(
         kGetAccessTokenBodyWithScopeFormat,
         enc_client_id.c_str(),
         enc_client_secret.c_str(),
diff --git a/google_apis/gaia/oauth2_api_call_flow.cc b/google_apis/gaia/oauth2_api_call_flow.cc
index f8a804d..a6a267c 100644
--- a/google_apis/gaia/oauth2_api_call_flow.cc
+++ b/google_apis/gaia/oauth2_api_call_flow.cc
@@ -28,7 +28,7 @@ static const char kAuthorizationHeaderFormat[] =
     "Authorization: Bearer %s";
 
 static std::string MakeAuthorizationHeader(const std::string& auth_token) {
-  return StringPrintf(kAuthorizationHeaderFormat, auth_token.c_str());
+  return base::StringPrintf(kAuthorizationHeaderFormat, auth_token.c_str());
 }
 }  // namespace
 
diff --git a/google_apis/gaia/oauth2_mint_token_fetcher.cc b/google_apis/gaia/oauth2_mint_token_fetcher.cc
index 051f9ab..c5dfc05 100644
--- a/google_apis/gaia/oauth2_mint_token_fetcher.cc
+++ b/google_apis/gaia/oauth2_mint_token_fetcher.cc
@@ -163,7 +163,7 @@ GURL OAuth2MintTokenFetcher::MakeMintTokenUrl() {
 // static
 std::string OAuth2MintTokenFetcher::MakeMintTokenHeader(
     const std::string& access_token) {
-  return StringPrintf(kAuthorizationHeaderFormat, access_token.c_str());
+  return base::StringPrintf(kAuthorizationHeaderFormat, access_token.c_str());
 }
 
 // static
@@ -171,7 +171,7 @@ std::string OAuth2MintTokenFetcher::MakeMintTokenBody(
     const std::string& client_id,
     const std::vector<std::string>& scopes,
     const std::string& origin) {
-  return StringPrintf(
+  return base::StringPrintf(
       kOAuth2IssueTokenBodyFormat,
       net::EscapeUrlEncodedData(JoinString(scopes, ','), true).c_str(),
       net::EscapeUrlEncodedData(client_id, true).c_str(),
diff --git a/google_apis/gaia/oauth2_mint_token_flow.cc b/google_apis/gaia/oauth2_mint_token_flow.cc
index 88f2878a..42fc4ef 100644
--- a/google_apis/gaia/oauth2_mint_token_flow.cc
+++ b/google_apis/gaia/oauth2_mint_token_flow.cc
@@ -139,7 +139,7 @@ std::string OAuth2MintTokenFlow::CreateApiCallBody() {
       (parameters_.mode == MODE_MINT_TOKEN_NO_FORCE ||
        parameters_.mode == MODE_MINT_TOKEN_FORCE)
           ? kResponseTypeValueToken : kResponseTypeValueNone;
-  return StringPrintf(
+  return base::StringPrintf(
       kOAuth2IssueTokenBodyFormat,
       net::EscapeUrlEncodedData(force_value, true).c_str(),
       net::EscapeUrlEncodedData(response_type_value, true).c_str(),
diff --git a/google_apis/gaia/oauth2_revocation_fetcher.cc b/google_apis/gaia/oauth2_revocation_fetcher.cc
index f5c7df1..eeec213 100644
--- a/google_apis/gaia/oauth2_revocation_fetcher.cc
+++ b/google_apis/gaia/oauth2_revocation_fetcher.cc
@@ -154,7 +154,7 @@ GURL OAuth2RevocationFetcher::MakeRevocationUrl() {
 // static
 std::string OAuth2RevocationFetcher::MakeRevocationHeader(
     const std::string& access_token) {
-  return StringPrintf(kAuthorizationHeaderFormat, access_token.c_str());
+  return base::StringPrintf(kAuthorizationHeaderFormat, access_token.c_str());
 }
 
 // static
@@ -163,7 +163,7 @@ std::string OAuth2RevocationFetcher::MakeRevocationBody(
     const std::string& origin) {
   std::string enc_client_id = net::EscapeUrlEncodedData(client_id, true);
   std::string enc_origin = net::EscapeUrlEncodedData(origin, true);
-  return StringPrintf(
+  return base::StringPrintf(
       kRevocationBodyFormat,
       enc_client_id.c_str(),
       enc_origin.c_str());
diff --git a/google_apis/gaia/oauth_request_signer.cc b/google_apis/gaia/oauth_request_signer.cc
index 8e90ac8..b5d138f 100644
--- a/google_apis/gaia/oauth_request_signer.cc
+++ b/google_apis/gaia/oauth_request_signer.cc
@@ -79,12 +79,12 @@ const std::string SignatureMethodName(
 std::string BuildBaseString(const GURL& request_base_url,
                             OAuthRequestSigner::HttpMethod http_method,
                             const std::string& base_parameters) {
-  return StringPrintf("%s&%s&%s",
-                      HttpMethodName(http_method).c_str(),
-                      OAuthRequestSigner::Encode(
-                          request_base_url.spec()).c_str(),
-                      OAuthRequestSigner::Encode(
-                          base_parameters).c_str());
+  return base::StringPrintf("%s&%s&%s",
+                            HttpMethodName(http_method).c_str(),
+                            OAuthRequestSigner::Encode(
+                                request_base_url.spec()).c_str(),
+                            OAuthRequestSigner::Encode(
+                                base_parameters).c_str());
 }
 
 std::string BuildBaseStringParameters(
@@ -448,9 +448,10 @@ bool OAuthRequestSigner::SignAuthHeader(
       else
         signed_text += ", ";
       signed_text +=
-          StringPrintf("%s=\"%s\"",
-                       OAuthRequestSigner::Encode(param->first).c_str(),
-                       OAuthRequestSigner::Encode(param->second).c_str());
+          base::StringPrintf(
+              "%s=\"%s\"",
+              OAuthRequestSigner::Encode(param->first).c_str(),
+              OAuthRequestSigner::Encode(param->second).c_str());
     }
     *signed_text_return = signed_text;
   }
diff --git a/ipc/ipc_logging.cc b/ipc/ipc_logging.cc
index 21f14c1..0691a9a 100644
--- a/ipc/ipc_logging.cc
+++ b/ipc/ipc_logging.cc
@@ -241,7 +241,7 @@ void Logging::Log(const LogData& data) {
   if (enabled_on_stderr_) {
     std::string message_name;
     if (data.message_name.empty()) {
-      message_name = StringPrintf("[unknown type %d]", data.type);
+      message_name = base::StringPrintf("[unknown type %d]", data.type);
     } else {
       message_name = data.message_name;
     }
diff --git a/ipc/ipc_message_utils.cc b/ipc/ipc_message_utils.cc
index 718e759..f3e40fa 100644
--- a/ipc/ipc_message_utils.cc
+++ b/ipc/ipc_message_utils.cc
@@ -39,11 +39,12 @@ void LogBytes(const std::vector<CharType>& data, std::string* out) {
     if (isprint(data[i]))
       out->push_back(data[i]);
     else
-      out->append(StringPrintf("[%02X]", static_cast<unsigned char>(data[i])));
+      out->append(
+          base::StringPrintf("[%02X]", static_cast<unsigned char>(data[i])));
   }
   if (data.size() > kMaxBytesToLog) {
     out->append(
-        StringPrintf(" and %u more bytes",
+        base::StringPrintf(" and %u more bytes",
                      static_cast<unsigned>(data.size() - kMaxBytesToLog)));
   }
 #endif
@@ -309,7 +310,7 @@ bool ParamTraits<float>::Read(const Message* m, PickleIterator* iter,
 }
 
 void ParamTraits<float>::Log(const param_type& p, std::string* l) {
-  l->append(StringPrintf("%e", p));
+  l->append(base::StringPrintf("%e", p));
 }
 
 void ParamTraits<double>::Write(Message* m, const param_type& p) {
@@ -330,7 +331,7 @@ bool ParamTraits<double>::Read(const Message* m, PickleIterator* iter,
 }
 
 void ParamTraits<double>::Log(const param_type& p, std::string* l) {
-  l->append(StringPrintf("%e", p));
+  l->append(base::StringPrintf("%e", p));
 }
 
 
@@ -481,9 +482,9 @@ bool ParamTraits<base::FileDescriptor>::Read(const Message* m,
 void ParamTraits<base::FileDescriptor>::Log(const param_type& p,
                                             std::string* l) {
   if (p.auto_close) {
-    l->append(StringPrintf("FD(%d auto-close)", p.fd));
+    l->append(base::StringPrintf("FD(%d auto-close)", p.fd));
   } else {
-    l->append(StringPrintf("FD(%d)", p.fd));
+    l->append(base::StringPrintf("FD(%d)", p.fd));
   }
 }
 #endif  // defined(OS_POSIX)
@@ -668,7 +669,7 @@ bool ParamTraits<IPC::ChannelHandle>::Read(const Message* m,
 
 void ParamTraits<IPC::ChannelHandle>::Log(const param_type& p,
                                           std::string* l) {
-  l->append(StringPrintf("ChannelHandle(%s", p.name.c_str()));
+  l->append(base::StringPrintf("ChannelHandle(%s", p.name.c_str()));
 #if defined(OS_POSIX)
   l->append(", ");
   ParamTraits<base::FileDescriptor>::Log(p.socket, l);
@@ -768,7 +769,7 @@ bool ParamTraits<HANDLE>::Read(const Message* m, PickleIterator* iter,
 }
 
 void ParamTraits<HANDLE>::Log(const param_type& p, std::string* l) {
-  l->append(StringPrintf("0x%X", p));
+  l->append(base::StringPrintf("0x%X", p));
 }
 
 void ParamTraits<LOGFONT>::Write(Message* m, const param_type& p) {
@@ -792,7 +793,7 @@ bool ParamTraits<LOGFONT>::Read(const Message* m, PickleIterator* iter,
 }
 
 void ParamTraits<LOGFONT>::Log(const param_type& p, std::string* l) {
-  l->append(StringPrintf("<LOGFONT>"));
+  l->append(base::StringPrintf("<LOGFONT>"));
 }
 
 void ParamTraits<MSG>::Write(Message* m, const param_type& p) {
diff --git a/media/video/capture/android/video_capture_device_android.cc b/media/video/capture/android/video_capture_device_android.cc
index d837b24..20601eb 100644
--- a/media/video/capture/android/video_capture_device_android.cc
+++ b/media/video/capture/android/video_capture_device_android.cc
@@ -52,7 +52,7 @@ void VideoCaptureDevice::GetDeviceNames(Names* device_names) {
         Java_ChromiumCameraInfo_getAt(env, camera_id);
 
     Name name;
-    name.unique_id = StringPrintf(
+    name.unique_id = base::StringPrintf(
         "%d", Java_ChromiumCameraInfo_getId(env, ci.obj()));
     name.device_name = base::android::ConvertJavaStringToUTF8(
         Java_ChromiumCameraInfo_getDeviceName(env, ci.obj()));
diff --git a/media/video/capture/fake_video_capture_device.cc b/media/video/capture/fake_video_capture_device.cc
index 8ca6860..addd172 100644
--- a/media/video/capture/fake_video_capture_device.cc
+++ b/media/video/capture/fake_video_capture_device.cc
@@ -28,8 +28,8 @@ void FakeVideoCaptureDevice::GetDeviceNames(Names* const device_names) {
 
   for (int n = 0; n < kNumberOfFakeDevices; n++) {
     Name name;
-    name.unique_id = StringPrintf("/dev/video%d", n);
-    name.device_name = StringPrintf("fake_device_%d", n);
+    name.unique_id = base::StringPrintf("/dev/video%d", n);
+    name.device_name = base::StringPrintf("fake_device_%d", n);
     device_names->push_back(name);
   }
 }
@@ -40,7 +40,7 @@ VideoCaptureDevice* FakeVideoCaptureDevice::Create(const Name& device_name) {
     return NULL;
   }
   for (int n = 0; n < kNumberOfFakeDevices; ++n) {
-    std::string possible_id = StringPrintf("/dev/video%d", n);
+    std::string possible_id = base::StringPrintf("/dev/video%d", n);
     if (device_name.unique_id.compare(possible_id) == 0) {
       return new FakeVideoCaptureDevice(device_name);
     }
diff --git a/media/video/capture/linux/video_capture_device_linux.cc b/media/video/capture/linux/video_capture_device_linux.cc
index d4db951..d3655db 100644
--- a/media/video/capture/linux/video_capture_device_linux.cc
+++ b/media/video/capture/linux/video_capture_device_linux.cc
@@ -126,7 +126,7 @@ void VideoCaptureDevice::GetDeviceNames(Names* device_names) {
         !(cap.capabilities & V4L2_CAP_VIDEO_OUTPUT)) {
       // This is a V4L2 video capture device
       if (HasUsableFormats(fd)) {
-        name.device_name = StringPrintf("%s", cap.card);
+        name.device_name = base::StringPrintf("%s", cap.card);
         device_names->push_back(name);
       } else {
         DVLOG(1) << "No usable formats reported by " << info.filename;
@@ -418,8 +418,8 @@ void VideoCaptureDeviceLinux::OnCaptureTask() {
 
       // Enqueue the buffer again.
       if (ioctl(device_fd_, VIDIOC_QBUF, &buffer) == -1) {
-        SetErrorState(
-            StringPrintf("Failed to enqueue capture buffer errno %d", errno));
+        SetErrorState(base::StringPrintf(
+            "Failed to enqueue capture buffer errno %d", errno));
       }
     }  // Else wait for next event.
   }
diff --git a/net/base/crl_set.cc b/net/base/crl_set.cc
index dd73c7e..735bb5e 100644
--- a/net/base/crl_set.cc
+++ b/net/base/crl_set.cc
@@ -459,7 +459,7 @@ bool CRLSet::GetIsDeltaUpdate(const base::StringPiece& in_data,
 }
 
 std::string CRLSet::Serialize() const {
-  std::string header = StringPrintf(
+  std::string header = base::StringPrintf(
       "{"
       "\"Version\":0,"
       "\"ContentType\":\"CRLSet\","
@@ -481,7 +481,7 @@ std::string CRLSet::Serialize() const {
   }
   header += "]";
   if (not_after_ != 0)
-    header += StringPrintf(",\"NotAfter\":%" PRIu64, not_after_);
+    header += base::StringPrintf(",\"NotAfter\":%" PRIu64, not_after_);
   header += "}";
 
   size_t len = 2 /* header len */ + header.size();
diff --git a/net/cookies/cookie_monster_unittest.cc b/net/cookies/cookie_monster_unittest.cc
index 1e8d83a..116d486 100644
--- a/net/cookies/cookie_monster_unittest.cc
+++ b/net/cookies/cookie_monster_unittest.cc
@@ -357,7 +357,7 @@ class CookieMonsterTest : public CookieStoreTest<CookieMonsterTestTraits> {
   CookieMonster* CreateMonsterForGC(int num_cookies) {
     CookieMonster* cm(new CookieMonster(NULL, NULL));
     for (int i = 0; i < num_cookies; i++) {
-      SetCookie(cm, GURL(StringPrintf("http://h%05d.izzle", i)), "a=1");
+      SetCookie(cm, GURL(base::StringPrintf("http://h%05d.izzle", i)), "a=1");
     }
     return cm;
   }
diff --git a/net/disk_cache/backend_unittest.cc b/net/disk_cache/backend_unittest.cc
index db33c8e..824a048 100644
--- a/net/disk_cache/backend_unittest.cc
+++ b/net/disk_cache/backend_unittest.cc
@@ -649,7 +649,7 @@ TEST_F(DiskCacheBackendTest, NewEvictionTrim) {
 
   disk_cache::Entry* entry;
   for (int i = 0; i < 100; i++) {
-    std::string name(StringPrintf("Key %d", i));
+    std::string name(base::StringPrintf("Key %d", i));
     ASSERT_EQ(net::OK, CreateEntry(name, &entry));
     entry->Close();
     if (i < 90) {
@@ -2652,7 +2652,7 @@ TEST_F(DiskCacheBackendTest, UpdateRankForExternalCacheHit) {
   disk_cache::Entry* entry;
 
   for (int i = 0; i < 2; ++i) {
-    std::string key = StringPrintf("key%d", i);
+    std::string key = base::StringPrintf("key%d", i);
     ASSERT_EQ(net::OK, CreateEntry(key, &entry));
     entry->Close();
   }
@@ -2676,7 +2676,7 @@ TEST_F(DiskCacheBackendTest, ShaderCacheUpdateRankForExternalCacheHit) {
   disk_cache::Entry* entry;
 
   for (int i = 0; i < 2; ++i) {
-    std::string key = StringPrintf("key%d", i);
+    std::string key = base::StringPrintf("key%d", i);
     ASSERT_EQ(net::OK, CreateEntry(key, &entry));
     entry->Close();
   }
diff --git a/net/disk_cache/simple/simple_synchronous_entry.cc b/net/disk_cache/simple/simple_synchronous_entry.cc
index 8dfa363..9f5c91b 100644
--- a/net/disk_cache/simple/simple_synchronous_entry.cc
+++ b/net/disk_cache/simple/simple_synchronous_entry.cc
@@ -41,12 +41,12 @@ namespace {
 
 std::string GetFilenameForKeyAndIndex(const std::string& key, int index) {
   const std::string sha_hash = base::SHA1HashString(key);
-  return StringPrintf("%02x%02x%02x%02x%02x_%1d",
-                      implicit_cast<unsigned char>(sha_hash[0]),
-                      implicit_cast<unsigned char>(sha_hash[1]),
-                      implicit_cast<unsigned char>(sha_hash[2]),
-                      implicit_cast<unsigned char>(sha_hash[3]),
-                      implicit_cast<unsigned char>(sha_hash[4]), index);
+  return base::StringPrintf("%02x%02x%02x%02x%02x_%1d",
+                            implicit_cast<unsigned char>(sha_hash[0]),
+                            implicit_cast<unsigned char>(sha_hash[1]),
+                            implicit_cast<unsigned char>(sha_hash[2]),
+                            implicit_cast<unsigned char>(sha_hash[3]),
+                            implicit_cast<unsigned char>(sha_hash[4]), index);
 }
 
 int32 DataSizeFromKeyAndFileSize(size_t key_size, int64 file_size) {
diff --git a/net/http/http_pipelined_network_transaction_unittest.cc b/net/http/http_pipelined_network_transaction_unittest.cc
index 2fe20f4..a2e9337 100644
--- a/net/http/http_pipelined_network_transaction_unittest.cc
+++ b/net/http/http_pipelined_network_transaction_unittest.cc
@@ -112,7 +112,7 @@ class HttpPipelinedNetworkTransactionTest : public testing::Test {
 
   HttpRequestInfo* GetRequestInfo(
       const char* filename, RequestInfoOptions options = REQUEST_DEFAULT) {
-    std::string url = StringPrintf("http://localhost/%s", filename);
+    std::string url = base::StringPrintf("http://localhost/%s", filename);
     HttpRequestInfo* request_info = new HttpRequestInfo;
     request_info->url = GURL(url);
     request_info->method = "GET";
diff --git a/net/http/proxy_client_socket.cc b/net/http/proxy_client_socket.cc
index 8882f42..b892479 100644
--- a/net/http/proxy_client_socket.cc
+++ b/net/http/proxy_client_socket.cc
@@ -27,7 +27,7 @@ void ProxyClientSocket::BuildTunnelRequest(
   // RFC 2616 Section 9 says the Host request-header field MUST accompany all
   // HTTP/1.1 requests.  Add "Proxy-Connection: keep-alive" for compat with
   // HTTP/1.0 proxies such as Squid (required for NTLM authentication).
-  *request_line = StringPrintf(
+  *request_line = base::StringPrintf(
       "CONNECT %s HTTP/1.1\r\n", endpoint.ToString().c_str());
   request_headers->SetHeader(HttpRequestHeaders::kHost,
                              GetHostAndOptionalPort(request_info.url));
diff --git a/net/proxy/proxy_resolver_v8_tracing.cc b/net/proxy/proxy_resolver_v8_tracing.cc
index 608d3cb..198418f 100644
--- a/net/proxy/proxy_resolver_v8_tracing.cc
+++ b/net/proxy/proxy_resolver_v8_tracing.cc
@@ -953,7 +953,7 @@ HostResolver::RequestInfo ProxyResolverV8Tracing::Job::MakeDnsRequestInfo(
 
 std::string ProxyResolverV8Tracing::Job::MakeDnsCacheKey(
     const std::string& host, ResolveDnsOperation op) {
-  return StringPrintf("%d:%s", op, host.c_str());
+  return base::StringPrintf("%d:%s", op, host.c_str());
 }
 
 void ProxyResolverV8Tracing::Job::HandleAlertOrError(bool is_alert,
diff --git a/net/proxy/proxy_resolver_v8_tracing_unittest.cc b/net/proxy/proxy_resolver_v8_tracing_unittest.cc
index 1c6aa13..e0162d4 100644
--- a/net/proxy/proxy_resolver_v8_tracing_unittest.cc
+++ b/net/proxy/proxy_resolver_v8_tracing_unittest.cc
@@ -74,8 +74,8 @@ class MockErrorObserver : public ProxyResolverErrorObserver {
                                 const string16& error) OVERRIDE {
     {
       base::AutoLock l(lock_);
-      output += StringPrintf("Error: line %d: %s\n", line_number,
-                             UTF16ToASCII(error).c_str());
+      output += base::StringPrintf("Error: line %d: %s\n", line_number,
+                                   UTF16ToASCII(error).c_str());
     }
     event_.Signal();
   }
diff --git a/net/test/python_utils_unittest.cc b/net/test/python_utils_unittest.cc
index 6d5a041..09f6630 100644
--- a/net/test/python_utils_unittest.cc
+++ b/net/test/python_utils_unittest.cc
@@ -52,7 +52,7 @@ TEST(PythonUtils, PythonRunTime) {
   // we want.
   cmd_line.AppendArg("-c");
   std::string input("PythonUtilsTest");
-  std::string python_cmd = StringPrintf("print '%s';", input.c_str());
+  std::string python_cmd = base::StringPrintf("print '%s';", input.c_str());
   cmd_line.AppendArg(python_cmd);
   std::string output;
   EXPECT_TRUE(base::GetAppOutput(cmd_line, &output));
diff --git a/net/url_request/url_request_unittest.cc b/net/url_request/url_request_unittest.cc
index 269e86c..32b99ac 100644
--- a/net/url_request/url_request_unittest.cc
+++ b/net/url_request/url_request_unittest.cc
@@ -4253,8 +4253,8 @@ TEST_F(HTTPSRequestTest, HTTPSPreloadedHSTSTest) {
   context.Init();
 
   TestDelegate d;
-  URLRequest r(GURL(StringPrintf("https://www.google.com:%d",
-                                 test_server.host_port_pair().port())),
+  URLRequest r(GURL(base::StringPrintf("https://www.google.com:%d",
+                                       test_server.host_port_pair().port())),
                &d,
                &context);
 
@@ -4300,8 +4300,8 @@ TEST_F(HTTPSRequestTest, HTTPSErrorsNoClobberTSSTest) {
   context.Init();
 
   TestDelegate d;
-  URLRequest r(GURL(StringPrintf("https://www.google.com:%d",
-                                 test_server.host_port_pair().port())),
+  URLRequest r(GURL(base::StringPrintf("https://www.google.com:%d",
+                                       test_server.host_port_pair().port())),
                &d,
                &context);
 
@@ -4366,8 +4366,8 @@ TEST_F(HTTPSRequestTest, HSTSPreservesPosts) {
   // cause a certificate error.  Ignore the error.
   d.set_allow_certificate_errors(true);
 
-  URLRequest req(GURL(StringPrintf("http://www.somewhere.com:%d/echo",
-                                   test_server.host_port_pair().port())),
+  URLRequest req(GURL(base::StringPrintf("http://www.somewhere.com:%d/echo",
+                                         test_server.host_port_pair().port())),
                  &d,
                  &context);
   req.set_method("POST");
diff --git a/net/websockets/websocket_frame_unittest.cc b/net/websockets/websocket_frame_unittest.cc
index 6934fad..800ae42 100644
--- a/net/websockets/websocket_frame_unittest.cc
+++ b/net/websockets/websocket_frame_unittest.cc
@@ -402,8 +402,8 @@ class WebSocketFrameTestMaskBenchmark : public testing::Test {
         1000 * (TimeTicks::HighResNow() - start).InMillisecondsF() /
         iterations_;
     LOG(INFO) << "Payload size " << size
-              << StringPrintf(" took %.03f microseconds per iteration",
-                              total_time_ms);
+              << base::StringPrintf(" took %.03f microseconds per iteration",
+                                    total_time_ms);
   }
 
  private:
diff --git a/printing/printed_document.cc b/printing/printed_document.cc
index 714f13d..22e0fd6 100644
--- a/printing/printed_document.cc
+++ b/printing/printed_document.cc
@@ -179,7 +179,7 @@ void PrintedDocument::DebugDump(const PrintedPage& page) {
   string16 filename;
   filename += name();
   filename += ASCIIToUTF16("_");
-  filename += ASCIIToUTF16(StringPrintf("%02d", page.page_number()));
+  filename += ASCIIToUTF16(base::StringPrintf("%02d", page.page_number()));
 #if defined(OS_WIN)
   filename += ASCIIToUTF16("_.emf");
   page.metafile()->SaveTo(
diff --git a/remoting/base/util.cc b/remoting/base/util.cc
index 31dda25..5873422 100644
--- a/remoting/base/util.cc
+++ b/remoting/base/util.cc
@@ -25,9 +25,9 @@ std::string GetTimestampString() {
   base::Time t = base::Time::NowFromSystemTime();
   base::Time::Exploded tex;
   t.LocalExplode(&tex);
-  return StringPrintf("%02d%02d/%02d%02d%02d:",
-                      tex.month, tex.day_of_month,
-                      tex.hour, tex.minute, tex.second);
+  return base::StringPrintf("%02d%02d/%02d%02d%02d:",
+                            tex.month, tex.day_of_month,
+                            tex.hour, tex.minute, tex.second);
 }
 
 int CalculateRGBOffset(int x, int y, int stride) {
diff --git a/remoting/host/setup/daemon_installer_win.cc b/remoting/host/setup/daemon_installer_win.cc
index 67c30a4..bc914b4 100644
--- a/remoting/host/setup/daemon_installer_win.cc
+++ b/remoting/host/setup/daemon_installer_win.cc
@@ -295,10 +295,10 @@ void DaemonCommandLineInstallerWin::Install() {
 
   // Launch the updater process and wait for its termination.
   string16 command_line = WideToUTF16(
-      StringPrintf(kGoogleUpdateCommandLineFormat,
-                   google_update.c_str(),
-                   kHostOmahaAppid,
-                   kOmahaLanguage));
+      base::StringPrintf(kGoogleUpdateCommandLineFormat,
+                         google_update.c_str(),
+                         kHostOmahaAppid,
+                         kOmahaLanguage));
 
   base::LaunchOptions options;
   if (!base::LaunchProcess(command_line, options, process_.Receive())) {
diff --git a/remoting/host/usage_stats_consent_win.cc b/remoting/host/usage_stats_consent_win.cc
index fa7345b..fea3853 100644
--- a/remoting/host/usage_stats_consent_win.cc
+++ b/remoting/host/usage_stats_consent_win.cc
@@ -25,9 +25,9 @@ const wchar_t kOmahaUsagestatsValue[] = L"usagestats";
 
 LONG ReadUsageStatsValue(const wchar_t* state_key, DWORD* usagestats_out) {
   // presubmit: allow wstring
-  std::wstring client_state = StringPrintf(kOmahaClientStateKeyFormat,
-                                           state_key,
-                                           remoting::kHostOmahaAppid);
+  std::wstring client_state = base::StringPrintf(kOmahaClientStateKeyFormat,
+                                                 state_key,
+                                                 remoting::kHostOmahaAppid);
   base::win::RegKey key;
   LONG result = key.Open(HKEY_LOCAL_MACHINE, client_state.c_str(), KEY_READ);
   if (result != ERROR_SUCCESS) {
@@ -73,9 +73,9 @@ bool IsUsageStatsAllowed() {
 bool SetUsageStatsConsent(bool allowed) {
   DWORD value = allowed;
   // presubmit: allow wstring
-  std::wstring client_state = StringPrintf(kOmahaClientStateKeyFormat,
-                                           kOmahaClientStateMedium,
-                                           kHostOmahaAppid);
+  std::wstring client_state = base::StringPrintf(kOmahaClientStateKeyFormat,
+                                                 kOmahaClientStateMedium,
+                                                 kHostOmahaAppid);
   base::win::RegKey key;
   LONG result = key.Create(HKEY_LOCAL_MACHINE, client_state.c_str(),
                            KEY_SET_VALUE);
diff --git a/remoting/host/win/launch_process_with_token.cc b/remoting/host/win/launch_process_with_token.cc
index fffa983..167ca9a 100644
--- a/remoting/host/win/launch_process_with_token.cc
+++ b/remoting/host/win/launch_process_with_token.cc
@@ -87,7 +87,7 @@ bool ConnectToExecutionServer(uint32 session_id,
   // Use the default pipe name if we couldn't query its name.
   if (pipe_name.empty()) {
     pipe_name = UTF8ToUTF16(
-        StringPrintf(kCreateProcessDefaultPipeNameFormat, session_id));
+        base::StringPrintf(kCreateProcessDefaultPipeNameFormat, session_id));
   }
 
   // Try to connect to the named pipe.
diff --git a/sql/connection.cc b/sql/connection.cc
index 0fda72e..5f6b590 100644
--- a/sql/connection.cc
+++ b/sql/connection.cc
@@ -240,7 +240,8 @@ bool Connection::Raze() {
         << " page_size_ " << page_size_ << " is not a power of two.";
     const int kSqliteMaxPageSize = 32768;  // from sqliteLimit.h
     DCHECK_LE(page_size_, kSqliteMaxPageSize);
-    const std::string sql = StringPrintf("PRAGMA page_size=%d", page_size_);
+    const std::string sql =
+        base::StringPrintf("PRAGMA page_size=%d", page_size_);
     if (!null_db.Execute(sql.c_str()))
       return false;
   }
@@ -666,13 +667,15 @@ bool Connection::OpenInternal(const std::string& file_name) {
         << " page_size_ " << page_size_ << " is not a power of two.";
     const int kSqliteMaxPageSize = 32768;  // from sqliteLimit.h
     DCHECK_LE(page_size_, kSqliteMaxPageSize);
-    const std::string sql = StringPrintf("PRAGMA page_size=%d", page_size_);
+    const std::string sql =
+        base::StringPrintf("PRAGMA page_size=%d", page_size_);
     if (!ExecuteWithTimeout(sql.c_str(), kBusyTimeout))
       DLOG(FATAL) << "Could not set page size: " << GetErrorMessage();
   }
 
   if (cache_size_ != 0) {
-    const std::string sql = StringPrintf("PRAGMA cache_size=%d", cache_size_);
+    const std::string sql =
+        base::StringPrintf("PRAGMA cache_size=%d", cache_size_);
     if (!ExecuteWithTimeout(sql.c_str(), kBusyTimeout))
       DLOG(FATAL) << "Could not set cache size: " << GetErrorMessage();
   }
diff --git a/testing/android/native_test_launcher.cc b/testing/android/native_test_launcher.cc
index 57a918b..2fde7351 100644
--- a/testing/android/native_test_launcher.cc
+++ b/testing/android/native_test_launcher.cc
@@ -142,9 +142,9 @@ static void RunTests(JNIEnv* env,
     dup2(STDOUT_FILENO, STDERR_FILENO);
 
   if (command_line.HasSwitch(switches::kWaitForDebugger)) {
-    std::string msg = StringPrintf("Native test waiting for GDB because "
-                                   "flag %s was supplied",
-                                   switches::kWaitForDebugger);
+    std::string msg = base::StringPrintf("Native test waiting for GDB because "
+                                         "flag %s was supplied",
+                                         switches::kWaitForDebugger);
     __android_log_write(ANDROID_LOG_VERBOSE, kLogTag, msg.c_str());
     base::debug::WaitForDebugger(24 * 60 * 60, false);
   }
diff --git a/third_party/cacheinvalidation/overrides/google/cacheinvalidation/deps/string_util.h b/third_party/cacheinvalidation/overrides/google/cacheinvalidation/deps/string_util.h
index 80e894a..bae09a4 100644
--- a/third_party/cacheinvalidation/overrides/google/cacheinvalidation/deps/string_util.h
+++ b/third_party/cacheinvalidation/overrides/google/cacheinvalidation/deps/string_util.h
@@ -11,6 +11,7 @@
 namespace invalidation {
 
 using base::StringAppendV;
+using base::StringPrintf;
 
 inline std::string SimpleItoa(int v) {
   return base::IntToString(v);
diff --git a/ui/app_list/pagination_model_unittest.cc b/ui/app_list/pagination_model_unittest.cc
index a8ebe7c..cfb2d48 100644
--- a/ui/app_list/pagination_model_unittest.cc
+++ b/ui/app_list/pagination_model_unittest.cc
@@ -57,7 +57,7 @@ class TestPaginationModelObserver : public PaginationModelObserver {
   void AppendSelectedPage(int page) {
     if (selected_pages_.length())
       selected_pages_.append(std::string(" "));
-    selected_pages_.append(StringPrintf("%d", page));
+    selected_pages_.append(base::StringPrintf("%d", page));
   }
 
   // PaginationModelObserver overrides:
diff --git a/ui/aura/root_window_host_linux.cc b/ui/aura/root_window_host_linux.cc
index 22c8ada..a32b25c 100644
--- a/ui/aura/root_window_host_linux.cc
+++ b/ui/aura/root_window_host_linux.cc
@@ -329,7 +329,7 @@ RootWindowHostLinux::RootWindowHostLinux(const gfx::Rect& bounds)
   // window to broadcast.
   // TODO(jhorwich) Remove this once Chrome supports window-based broadcasting.
   static int root_window_number = 0;
-  std::string name = StringPrintf("aura_root_%d", root_window_number++);
+  std::string name = base::StringPrintf("aura_root_%d", root_window_number++);
   XStoreName(xdisplay_, xwindow_, name.c_str());
   XRRSelectInput(xdisplay_, x_root_window_,
                  RRScreenChangeNotifyMask | RROutputChangeNotifyMask);
diff --git a/ui/aura/test/test_window_delegate.cc b/ui/aura/test/test_window_delegate.cc
index 462cd70..f75d827 100644
--- a/ui/aura/test/test_window_delegate.cc
+++ b/ui/aura/test/test_window_delegate.cc
@@ -182,10 +182,10 @@ void EventCountDelegate::OnMouseEvent(ui::MouseEvent* event) {
 }
 
 std::string EventCountDelegate::GetMouseMotionCountsAndReset() {
-  std::string result = StringPrintf("%d %d %d",
-                                    mouse_enter_count_,
-                                    mouse_move_count_,
-                                    mouse_leave_count_);
+  std::string result = base::StringPrintf("%d %d %d",
+                                          mouse_enter_count_,
+                                          mouse_move_count_,
+                                          mouse_leave_count_);
   mouse_enter_count_ = 0;
   mouse_move_count_ = 0;
   mouse_leave_count_ = 0;
@@ -193,9 +193,9 @@ std::string EventCountDelegate::GetMouseMotionCountsAndReset() {
 }
 
 std::string EventCountDelegate::GetMouseButtonCountsAndReset() {
-  std::string result = StringPrintf("%d %d",
-                                    mouse_press_count_,
-                                    mouse_release_count_);
+  std::string result = base::StringPrintf("%d %d",
+                                          mouse_press_count_,
+                                          mouse_release_count_);
   mouse_press_count_ = 0;
   mouse_release_count_ = 0;
   return result;
@@ -203,9 +203,9 @@ std::string EventCountDelegate::GetMouseButtonCountsAndReset() {
 
 
 std::string EventCountDelegate::GetKeyCountsAndReset() {
-  std::string result = StringPrintf("%d %d",
-                                    key_press_count_,
-                                    key_release_count_);
+  std::string result = base::StringPrintf("%d %d",
+                                          key_press_count_,
+                                          key_release_count_);
   key_press_count_ = 0;
   key_release_count_ = 0;
   return result;
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index beb12cf..eef013c 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -628,7 +628,7 @@ void Window::OnDeviceScaleFactorChanged(float device_scale_factor) {
 
 #ifndef NDEBUG
 std::string Window::GetDebugInfo() const {
-  return StringPrintf(
+  return base::StringPrintf(
       "%s<%d> bounds(%d, %d, %d, %d) %s %s opacity=%.1f",
       name().empty() ? "Unknown" : name().c_str(), id(),
       bounds().x(), bounds().y(), bounds().width(), bounds().height(),
diff --git a/ui/base/keycodes/keyboard_code_conversion_x.cc b/ui/base/keycodes/keyboard_code_conversion_x.cc
index 9d79faf..7b75233 100644
--- a/ui/base/keycodes/keyboard_code_conversion_x.cc
+++ b/ui/base/keycodes/keyboard_code_conversion_x.cc
@@ -424,7 +424,7 @@ KeyboardCode KeyboardCodeFromXKeysym(unsigned int keysym) {
 
     // TODO(sad): some keycodes are still missing.
   }
-  DLOG(WARNING) << "Unknown keysym: " << StringPrintf("0x%x", keysym);
+  DLOG(WARNING) << "Unknown keysym: " << base::StringPrintf("0x%x", keysym);
   return VKEY_UNKNOWN;
 }
 
diff --git a/ui/base/x/x11_util.cc b/ui/base/x/x11_util.cc
index 38f0929..ffa9baf 100644
--- a/ui/base/x/x11_util.cc
+++ b/ui/base/x/x11_util.cc
@@ -1793,7 +1793,7 @@ void LogErrorEventDescription(Display* dpy,
       int ext_code, first_event, first_error;
       XQueryExtension(dpy, ext_list[i], &ext_code, &first_event, &first_error);
       if (error_event.request_code == ext_code) {
-        std::string msg = StringPrintf(
+        std::string msg = base::StringPrintf(
             "%s.%d", ext_list[i], error_event.minor_code);
         XGetErrorDatabaseText(
             dpy, "XRequest", msg.c_str(), "Unknown", request_str,
diff --git a/ui/compositor/layer_unittest.cc b/ui/compositor/layer_unittest.cc
index 6efe3a5..aaba292 100644
--- a/ui/compositor/layer_unittest.cc
+++ b/ui/compositor/layer_unittest.cc
@@ -169,7 +169,7 @@ class TestLayerDelegate : public LayerDelegate {
   int color_index() const { return color_index_; }
 
   std::string ToScaleString() const {
-    return StringPrintf("%.1f %.1f", scale_x_, scale_y_);
+    return base::StringPrintf("%.1f %.1f", scale_x_, scale_y_);
   }
 
   float device_scale_factor() const {
diff --git a/ui/message_center/notification_list_unittest.cc b/ui/message_center/notification_list_unittest.cc
index aa4ab66..6d4b551 100644
--- a/ui/message_center/notification_list_unittest.cc
+++ b/ui/message_center/notification_list_unittest.cc
@@ -59,8 +59,8 @@ class NotificationListTest : public testing::Test {
     std::string new_id = base::StringPrintf(kIdFormat, counter_);
     notification_list_->AddNotification(
         message_center::NOTIFICATION_TYPE_SIMPLE, new_id,
-        UTF8ToUTF16(StringPrintf(kTitleFormat, counter_)),
-        UTF8ToUTF16(StringPrintf(kMessageFormat, counter_)),
+        UTF8ToUTF16(base::StringPrintf(kTitleFormat, counter_)),
+        UTF8ToUTF16(base::StringPrintf(kMessageFormat, counter_)),
         UTF8ToUTF16(kDisplaySource), kExtensionId,
         optional_fields);
     counter_++;
diff --git a/ui/surface/accelerated_surface_transformer_win_unittest.cc b/ui/surface/accelerated_surface_transformer_win_unittest.cc
index e911281..1265e6e 100644
--- a/ui/surface/accelerated_surface_transformer_win_unittest.cc
+++ b/ui/surface/accelerated_surface_transformer_win_unittest.cc
@@ -124,7 +124,8 @@ class AcceleratedSurfaceTransformerTest : public testing::TestWithParam<int> {
     EXPECT_HRESULT_SUCCEEDED(device()->GetDirect3D(d3d.Receive()));
     D3DADAPTER_IDENTIFIER9 info;
     EXPECT_HRESULT_SUCCEEDED(d3d->GetAdapterIdentifier(0, 0, &info));
-    return StringPrintf("Running on graphics hardware: %s", info.Description);
+    return base::StringPrintf(
+        "Running on graphics hardware: %s", info.Description);
   }
 
   void SeedRandom(const char* seed) {
@@ -228,9 +229,9 @@ class AcceleratedSurfaceTransformerTest : public testing::TestWithParam<int> {
       return true;
 
     std::string expected_color =
-        StringPrintf("%3d, %3d, %3d, %3d", a[0], a[1], a[2], a[3]);
+        base::StringPrintf("%3d, %3d, %3d, %3d", a[0], a[1], a[2], a[3]);
     std::string actual_color =
-        StringPrintf("%3d, %3d, %3d, %3d", b[0], b[1], b[2], b[3]);
+        base::StringPrintf("%3d, %3d, %3d, %3d", b[0], b[1], b[2], b[3]);
     EXPECT_EQ(expected_color, actual_color)
         << "Componentwise color difference was "
         << max_error << "; max allowed is " << color_error_tolerance();
@@ -244,8 +245,9 @@ bool AssertSameColor(uint8 color_a, uint8 color_b) {
     int max_error = std::abs((int) color_a - (int) color_b);
     if (max_error <= color_error_tolerance())
       return true;
-    ADD_FAILURE() << "Colors not equal: " << StringPrintf("0x%x", color_a)
-                  << " vs. " << StringPrintf("0x%x", color_b);
+    ADD_FAILURE() << "Colors not equal: "
+                  << base::StringPrintf("0x%x", color_a)
+                  << " vs. " << base::StringPrintf("0x%x", color_b);
     return false;
   }
 
@@ -338,10 +340,11 @@ bool AssertSameColor(uint8 color_a, uint8 color_b) {
                             int checkerboard_size) {
 
     SCOPED_TRACE(
-        StringPrintf("Resizing %dx%d -> %dx%d at checkerboard size of %d",
-                     src_size.width(), src_size.height(),
-                     dst_size.width(), dst_size.height(),
-                     checkerboard_size));
+        base::StringPrintf(
+            "Resizing %dx%d -> %dx%d at checkerboard size of %d",
+            src_size.width(), src_size.height(),
+            dst_size.width(), dst_size.height(),
+            checkerboard_size));
 
     set_color_error_tolerance(4);
 
@@ -400,8 +403,8 @@ bool AssertSameColor(uint8 color_a, uint8 color_b) {
   void DoCopyInvertedTest(AcceleratedSurfaceTransformer* gpu_ops,
                           const gfx::Size& size) {
 
-    SCOPED_TRACE(
-        StringPrintf("CopyInverted @ %dx%d", size.width(), size.height()));
+    SCOPED_TRACE(base::StringPrintf(
+        "CopyInverted @ %dx%d", size.width(), size.height()));
 
     set_color_error_tolerance(0);
 
@@ -459,10 +462,11 @@ bool AssertSameColor(uint8 color_a, uint8 color_b) {
                            int checkerboard_size,
                            boolean use_multi_render_targets) {
     SCOPED_TRACE(
-        StringPrintf("YUV Converting %dx%d at checkerboard size of %d; MRT %s",
-                     src_size.width(), src_size.height(),
-                     checkerboard_size,
-                     use_multi_render_targets ? "enabled" : "disabled"));
+        base::StringPrintf(
+            "YUV Converting %dx%d at checkerboard size of %d; MRT %s",
+            src_size.width(), src_size.height(),
+            checkerboard_size,
+            use_multi_render_targets ? "enabled" : "disabled"));
 
 
     base::win::ScopedComPtr<IDirect3DTexture9> src;
@@ -686,7 +690,8 @@ TEST_P(AcceleratedSurfaceTransformerTest, LargeSurfaces) {
   ASSERT_HRESULT_SUCCEEDED(
       device()->GetDeviceCaps(&caps));
 
-  SCOPED_TRACE(StringPrintf("max texture size: %dx%d, max texture aspect: %d",
+  SCOPED_TRACE(base::StringPrintf(
+     "max texture size: %dx%d, max texture aspect: %d",
       caps.MaxTextureWidth, caps.MaxTextureHeight, caps.MaxTextureAspectRatio));
 
   const int w = caps.MaxTextureWidth;
diff --git a/webkit/fileapi/file_system_origin_database.cc b/webkit/fileapi/file_system_origin_database.cc
index 0300da2..ef0df54 100644
--- a/webkit/fileapi/file_system_origin_database.cc
+++ b/webkit/fileapi/file_system_origin_database.cc
@@ -229,7 +229,7 @@ bool FileSystemOriginDatabase::GetPathForOrigin(
     int last_path_number;
     if (!GetLastPathNumber(&last_path_number))
       return false;
-    path_string = StringPrintf("%03u", last_path_number + 1);
+    path_string = base::StringPrintf("%03u", last_path_number + 1);
     // store both back as a single transaction
     leveldb::WriteBatch batch;
     batch.Put(LastPathKey(), path_string);
diff --git a/webkit/fileapi/obfuscated_file_util.cc b/webkit/fileapi/obfuscated_file_util.cc
index 7031172..6f9a900 100644
--- a/webkit/fileapi/obfuscated_file_util.cc
+++ b/webkit/fileapi/obfuscated_file_util.cc
@@ -1323,14 +1323,15 @@ PlatformFileError ObfuscatedFileUtil::GenerateNewLocalPath(
   // We use the third- and fourth-to-last digits as the directory.
   int64 directory_number = number % 10000 / 100;
   new_local_path = new_local_path.AppendASCII(
-      StringPrintf("%02" PRId64, directory_number));
+      base::StringPrintf("%02" PRId64, directory_number));
 
   error = NativeFileUtil::CreateDirectory(
       new_local_path, false /* exclusive */, false /* recursive */);
   if (error != base::PLATFORM_FILE_OK)
     return error;
 
-  *local_path = new_local_path.AppendASCII(StringPrintf("%08" PRId64, number));
+  *local_path =
+      new_local_path.AppendASCII(base::StringPrintf("%08" PRId64, number));
   return base::PLATFORM_FILE_OK;
 }
 
diff --git a/webkit/media/cache_util_unittest.cc b/webkit/media/cache_util_unittest.cc
index bd2ff38..2703026 100644
--- a/webkit/media/cache_util_unittest.cc
+++ b/webkit/media/cache_util_unittest.cc
@@ -85,10 +85,10 @@ TEST(CacheUtilTest, GetReasonsForUncacheability) {
     },
   };
   for (size_t i = 0; i < arraysize(tests); ++i) {
-    SCOPED_TRACE(StringPrintf("case: %" PRIuS
-                              ", version: %d, code: %d, headers: %s",
-                              i, tests[i].version, tests[i].status_code,
-                              tests[i].headers));
+    SCOPED_TRACE(base::StringPrintf("case: %" PRIuS
+                                    ", version: %d, code: %d, headers: %s",
+                                    i, tests[i].version, tests[i].status_code,
+                                    tests[i].headers));
     EXPECT_EQ(GetReasonsForUncacheability(CreateResponse(tests[i])),
               tests[i].expected_reasons);
   }
author	groby@chromium.org <groby@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>	2013-03-18 22:33:04 +0000
committer	groby@chromium.org <groby@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>	2013-03-18 22:33:04 +0000
commit	7d3cbc90c089bb3ba5cb81a5abdc0846d5826def (patch)
tree	8ad0db2d4581c8e935ed1b07c6b4147a5350a204
parent	bb192b87059a76b89fbc20ad08347c28656e838d (diff)
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