Move StringPiece into the base namespace. It is colliding

with the StringPiece class in icu4.2, which is a problem
when trying to use the system version of icu.

Review URL: http://codereview.chromium.org/193072


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@25920 0039d316-1c4b-4281-b951-d872f2087c98

59 files changed, 194 insertions, 159 deletions

diff --git a/DEPS b/DEPS
index d96e830..ca243ba 100644
--- a/DEPS
+++ b/DEPS
@@ -28,7 +28,7 @@ deps = {
     "/trunk/deps/third_party/icu42@25717",
 
   "src/third_party/hunspell":
-   "/trunk/deps/third_party/hunspell128@25668",
+   "/trunk/deps/third_party/hunspell128@25906",
 
   "src/third_party/protobuf2/src":
     "http://protobuf.googlecode.com/svn/trunk@219",
diff --git a/app/resource_bundle.h b/app/resource_bundle.h
index 52c85c5..23f39c5 100644
--- a/app/resource_bundle.h
+++ b/app/resource_bundle.h
@@ -33,7 +33,9 @@ class Font;
 }
 class SkBitmap;
 typedef uint32 SkColor;
+namespace base {
 class StringPiece;
+}
 
 #if defined(OS_MACOSX)
 #ifdef __OBJC__
@@ -105,7 +107,7 @@ class ResourceBundle {
 
   // Like GetDataResource(), but avoids copying the resource.  Instead, it
   // returns a StringPiece which points into the actual resource in the image.
-  StringPiece GetRawDataResource(int resource_id);
+  base::StringPiece GetRawDataResource(int resource_id);
 
   // Get a localized string given a message id.  Returns an empty
   // string if the message_id is not found.
diff --git a/app/resource_bundle_linux.cc b/app/resource_bundle_linux.cc
index c84fa33..85f00c6 100644
--- a/app/resource_bundle_linux.cc
+++ b/app/resource_bundle_linux.cc
@@ -121,7 +121,7 @@ void ResourceBundle::LoadThemeResources() {
 bool ResourceBundle::LoadResourceBytes(DataHandle module, int resource_id,
                                        std::vector<unsigned char>* bytes) {
   DCHECK(module);
-  StringPiece data;
+  base::StringPiece data;
   if (!module->Get(resource_id, &data))
     return false;
 
@@ -131,11 +131,11 @@ bool ResourceBundle::LoadResourceBytes(DataHandle module, int resource_id,
   return true;
 }
 
-StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
+base::StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
   DCHECK(resources_data_);
-  StringPiece data;
+  base::StringPiece data;
   if (!resources_data_->Get(resource_id, &data))
-    return StringPiece();
+    return base::StringPiece();
   return data;
 }
 
@@ -147,7 +147,7 @@ string16 ResourceBundle::GetLocalizedString(int message_id) {
     return string16();
   }
 
-  StringPiece data;
+  base::StringPiece data;
   if (!locale_resources_data_->Get(message_id, &data)) {
     // Fall back on the main data pack (shouldn't be any strings here except in
     // unittests).
diff --git a/app/resource_bundle_mac.mm b/app/resource_bundle_mac.mm
index e96ed54..6696617 100644
--- a/app/resource_bundle_mac.mm
+++ b/app/resource_bundle_mac.mm
@@ -75,7 +75,7 @@ void ResourceBundle::LoadThemeResources() {
 bool ResourceBundle::LoadResourceBytes(DataHandle module, int resource_id,
                                        std::vector<unsigned char>* bytes) {
   DCHECK(module);
-  StringPiece data;
+  base::StringPiece data;
   if (!module->Get(resource_id, &data))
     return false;
 
@@ -85,11 +85,11 @@ bool ResourceBundle::LoadResourceBytes(DataHandle module, int resource_id,
   return true;
 }
 
-StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
+base::StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
   DCHECK(resources_data_);
-  StringPiece data;
+  base::StringPiece data;
   if (!resources_data_->Get(resource_id, &data))
-    return StringPiece();
+    return base::StringPiece();
   return data;
 }
 
@@ -101,7 +101,7 @@ string16 ResourceBundle::GetLocalizedString(int message_id) {
     return string16();
   }
 
-  StringPiece data;
+  base::StringPiece data;
   if (!locale_resources_data_->Get(message_id, &data)) {
     // Fall back on the main data pack (shouldn't be any strings here except in
     // unittests).
diff --git a/app/resource_bundle_win.cc b/app/resource_bundle_win.cc
index dcb669e..3526481 100644
--- a/app/resource_bundle_win.cc
+++ b/app/resource_bundle_win.cc
@@ -105,22 +105,22 @@ HICON ResourceBundle::LoadThemeIcon(int icon_id) {
   return ::LoadIcon(theme_data_, MAKEINTRESOURCE(icon_id));
 }
 
-StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
+base::StringPiece ResourceBundle::GetRawDataResource(int resource_id) {
   void* data_ptr;
   size_t data_size;
   if (base::GetDataResourceFromModule(_AtlBaseModule.GetModuleInstance(),
                                       resource_id,
                                       &data_ptr,
                                       &data_size)) {
-    return StringPiece(static_cast<const char*>(data_ptr), data_size);
+    return base::StringPiece(static_cast<const char*>(data_ptr), data_size);
   } else if (locale_resources_data_ &&
              base::GetDataResourceFromModule(locale_resources_data_,
                                              resource_id,
                                              &data_ptr,
                                              &data_size)) {
-    return StringPiece(static_cast<const char*>(data_ptr), data_size);
+    return base::StringPiece(static_cast<const char*>(data_ptr), data_size);
   }
-  return StringPiece();
+  return base::StringPiece();
 }
 
 // Loads and returns a cursor from the current module.
diff --git a/base/data_pack.h b/base/data_pack.h
index ff4f6d9..02a3849 100644
--- a/base/data_pack.h
+++ b/base/data_pack.h
@@ -16,10 +16,11 @@ namespace file_util {
   class MemoryMappedFile;
 }
 class FilePath;
-class StringPiece;
 
 namespace base {
 
+class StringPiece;
+
 class DataPack {
  public:
   DataPack();
diff --git a/base/data_pack_unittest.cc b/base/data_pack_unittest.cc
index 71c37e5..7c2cfeb 100644
--- a/base/data_pack_unittest.cc
+++ b/base/data_pack_unittest.cc
@@ -24,7 +24,7 @@ TEST_F(DataPackTest, Load) {
   base::DataPack pack;
   ASSERT_TRUE(pack.Load(data_path_));
 
-  StringPiece data;
+  base::StringPiece data;
   ASSERT_TRUE(pack.Get(4, &data));
   EXPECT_EQ("this is id 4", data);
   ASSERT_TRUE(pack.Get(6, &data));
diff --git a/base/debug_util_posix.cc b/base/debug_util_posix.cc
index dd22710..081f4c4 100644
--- a/base/debug_util_posix.cc
+++ b/base/debug_util_posix.cc
@@ -92,11 +92,11 @@ bool DebugUtil::BeingDebugged() {
   if (num_read <= 0)
     return false;
 
-  StringPiece status(buf, num_read);
-  StringPiece tracer("TracerPid:\t");
+  base::StringPiece status(buf, num_read);
+  base::StringPiece tracer("TracerPid:\t");
 
-  StringPiece::size_type pid_index = status.find(tracer);
-  if (pid_index == StringPiece::npos)
+  base::StringPiece::size_type pid_index = status.find(tracer);
+  if (pid_index == base::StringPiece::npos)
     return false;
 
   // Our pid is 0 without a debugger, assume this for any pid starting with 0.
diff --git a/base/file_path.cc b/base/file_path.cc
index 222b225..a521b37 100644
--- a/base/file_path.cc
+++ b/base/file_path.cc
@@ -310,7 +310,8 @@ FilePath FilePath::InsertBeforeExtension(const StringType& suffix) const {
   return FilePath(ret);
 }
 
-FilePath FilePath::InsertBeforeExtensionASCII(const StringPiece& suffix) const {
+FilePath FilePath::InsertBeforeExtensionASCII(const base::StringPiece& suffix)
+    const {
   DCHECK(IsStringASCII(suffix));
 #if defined(OS_WIN)
   return InsertBeforeExtension(ASCIIToWide(suffix));
@@ -397,7 +398,7 @@ FilePath FilePath::Append(const FilePath& component) const {
   return Append(component.value());
 }
 
-FilePath FilePath::AppendASCII(const StringPiece& component) const {
+FilePath FilePath::AppendASCII(const base::StringPiece& component) const {
   DCHECK(IsStringASCII(component));
 #if defined(OS_WIN)
   return Append(ASCIIToWide(component));
diff --git a/base/file_path.h b/base/file_path.h
index 0b2ba5c..b608651 100644
--- a/base/file_path.h
+++ b/base/file_path.h
@@ -187,7 +187,7 @@ class FilePath {
   // path == "C:\pics\jojo"     suffix == " (1)", returns "C:\pics\jojo (1)"
   // path == "C:\pics.old\jojo" suffix == " (1)", returns "C:\pics.old\jojo (1)"
   FilePath InsertBeforeExtension(const StringType& suffix) const;
-  FilePath InsertBeforeExtensionASCII(const StringPiece& suffix) const;
+  FilePath InsertBeforeExtensionASCII(const base::StringPiece& suffix) const;
 
   // Replaces the extension of |file_name| with |extension|.  If |file_name|
   // does not have an extension, them |extension| is added.  If |extension| is
@@ -214,7 +214,8 @@ class FilePath {
   // On Linux, although it can use any 8-bit encoding for paths, we assume that
   // ASCII is a valid subset, regardless of the encoding, since many operating
   // system paths will always be ASCII.
-  FilePath AppendASCII(const StringPiece& component) const WARN_UNUSED_RESULT;
+  FilePath AppendASCII(const base::StringPiece& component)
+      const WARN_UNUSED_RESULT;
 
   // Returns true if this FilePath contains an absolute path.  On Windows, an
   // absolute path begins with either a drive letter specification followed by
diff --git a/base/string_piece.cc b/base/string_piece.cc
index 1acb0cb..6844892 100644
--- a/base/string_piece.cc
+++ b/base/string_piece.cc
@@ -8,6 +8,8 @@
 
 #include "base/string_piece.h"
 
+namespace base {
+
 typedef StringPiece::size_type size_type;
 
 std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
@@ -213,3 +215,5 @@ StringPiece StringPiece::substr(size_type pos, size_type n) const {
 }
 
 const StringPiece::size_type StringPiece::npos = size_type(-1);
+
+}  // namespace base
diff --git a/base/string_piece.h b/base/string_piece.h
index fe10806..47d4968 100644
--- a/base/string_piece.h
+++ b/base/string_piece.h
@@ -24,6 +24,8 @@
 
 #include "base/basictypes.h"
 
+namespace base {
+
 class StringPiece {
  public:
   typedef size_t size_type;
@@ -181,4 +183,6 @@ inline bool operator>=(const StringPiece& x, const StringPiece& y) {
 // allow StringPiece to be logged (needed for unit testing).
 extern std::ostream& operator<<(std::ostream& o, const StringPiece& piece);
 
+}  // namespace base
+
 #endif  // BASE_STRING_PIECE_H_
diff --git a/base/string_piece_unittest.cc b/base/string_piece_unittest.cc
index ff62d46..8289cf3 100644
--- a/base/string_piece_unittest.cc
+++ b/base/string_piece_unittest.cc
@@ -8,6 +8,8 @@
 
 #include "testing/gtest/include/gtest/gtest.h"
 
+using namespace base;
+
 TEST(StringPieceTest, CheckComparisonOperators) {
 #define CMP_Y(op, x, y)                                               \
   ASSERT_TRUE( (StringPiece((x)) op StringPiece((y))));               \
diff --git a/base/string_util.cc b/base/string_util.cc
index 82b6c0b..fd33ef0 100644
--- a/base/string_util.cc
+++ b/base/string_util.cc
@@ -506,7 +506,7 @@ std::string WideToASCII(const std::wstring& wide) {
   return std::string(wide.begin(), wide.end());
 }
 
-std::wstring ASCIIToWide(const StringPiece& ascii) {
+std::wstring ASCIIToWide(const base::StringPiece& ascii) {
   DCHECK(IsStringASCII(ascii)) << ascii;
   return std::wstring(ascii.begin(), ascii.end());
 }
@@ -516,7 +516,7 @@ std::string UTF16ToASCII(const string16& utf16) {
   return std::string(utf16.begin(), utf16.end());
 }
 
-string16 ASCIIToUTF16(const StringPiece& ascii) {
+string16 ASCIIToUTF16(const base::StringPiece& ascii) {
   DCHECK(IsStringASCII(ascii)) << ascii;
   return string16(ascii.begin(), ascii.end());
 }
@@ -563,7 +563,7 @@ bool IsStringASCII(const string16& str) {
 }
 #endif
 
-bool IsStringASCII(const StringPiece& str) {
+bool IsStringASCII(const base::StringPiece& str) {
   return DoIsStringASCII(str);
 }
 
@@ -745,7 +745,7 @@ bool LowerCaseEqualsASCII(const wchar_t* a_begin,
   return DoLowerCaseEqualsASCII(a_begin, a_end, b);
 }
 
-bool EqualsASCII(const string16& a, const StringPiece& b) {
+bool EqualsASCII(const string16& a, const base::StringPiece& b) {
   if (a.length() != b.length())
     return false;
   return std::equal(b.begin(), b.end(), a.begin());
diff --git a/base/string_util.h b/base/string_util.h
index d1767f9..9143346 100644
--- a/base/string_util.h
+++ b/base/string_util.h
@@ -176,9 +176,9 @@ std::string CollapseWhitespaceASCII(const std::string& text,
 
 // These convert between ASCII (7-bit) and Wide/UTF16 strings.
 std::string WideToASCII(const std::wstring& wide);
-std::wstring ASCIIToWide(const StringPiece& ascii);
+std::wstring ASCIIToWide(const base::StringPiece& ascii);
 std::string UTF16ToASCII(const string16& utf16);
-string16 ASCIIToUTF16(const StringPiece& ascii);
+string16 ASCIIToUTF16(const base::StringPiece& ascii);
 
 // These convert between UTF-8, -16, and -32 strings. They are potentially slow,
 // so avoid unnecessary conversions. The low-level versions return a boolean
@@ -196,7 +196,7 @@ string16 ASCIIToUTF16(const StringPiece& ascii);
 bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output);
 std::string WideToUTF8(const std::wstring& wide);
 bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output);
-std::wstring UTF8ToWide(const StringPiece& utf8);
+std::wstring UTF8ToWide(const base::StringPiece& utf8);
 
 bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output);
 string16 WideToUTF16(const std::wstring& wide);
@@ -287,7 +287,7 @@ bool IsString8Bit(const std::wstring& str);
 bool IsStringUTF8(const std::string& str);
 bool IsStringWideUTF8(const std::wstring& str);
 bool IsStringASCII(const std::wstring& str);
-bool IsStringASCII(const StringPiece& str);
+bool IsStringASCII(const base::StringPiece& str);
 bool IsStringASCII(const string16& str);
 
 // ASCII-specific tolower.  The standard library's tolower is locale sensitive,
@@ -353,7 +353,7 @@ bool LowerCaseEqualsASCII(const wchar_t* a_begin,
 
 // Performs a case-sensitive string compare. The behavior is undefined if both
 // strings are not ASCII.
-bool EqualsASCII(const string16& a, const StringPiece& b);
+bool EqualsASCII(const string16& a, const base::StringPiece& b);
 
 // Returns true if str starts with search, or false otherwise.
 bool StartsWithASCII(const std::string& str,
diff --git a/base/string_util_icu.cc b/base/string_util_icu.cc
index a043e97..d3c9edf 100644
--- a/base/string_util_icu.cc
+++ b/base/string_util_icu.cc
@@ -333,7 +333,7 @@ bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output) {
   return ConvertUnicode<wchar_t, std::string>(src, src_len, output);
 }
 
-std::wstring UTF8ToWide(const StringPiece& utf8) {
+std::wstring UTF8ToWide(const base::StringPiece& utf8) {
   std::wstring ret;
   if (utf8.empty())
     return ret;
diff --git a/base/sys_string_conversions.h b/base/sys_string_conversions.h
index 420c301..18be826 100644
--- a/base/sys_string_conversions.h
+++ b/base/sys_string_conversions.h
@@ -22,10 +22,10 @@ class NSString;
 #endif
 #endif  // OS_MACOSX
 
-class StringPiece;
-
 namespace base {
 
+class StringPiece;
+
 // Converts between wide and UTF-8 representations of a string. On error, the
 // result is system-dependent.
 std::string SysWideToUTF8(const std::wstring& wide);
diff --git a/chrome/browser/browser_about_handler.cc b/chrome/browser/browser_about_handler.cc
index c7805eb..047ca97 100644
--- a/chrome/browser/browser_about_handler.cc
+++ b/chrome/browser/browser_about_handler.cc
@@ -247,7 +247,7 @@ std::string AboutPlugins() {
   localized_strings.SetString(L"enabled_no",
       l10n_util::GetString(IDS_ABOUT_PLUGINS_ENABLED_NO));
 
-  static const StringPiece plugins_html(
+  static const base::StringPiece plugins_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_ABOUT_PLUGINS_HTML));
 
@@ -348,7 +348,7 @@ std::string AboutStats() {
   }
 
   // Get about_stats.html
-  static const StringPiece stats_html(
+  static const base::StringPiece stats_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_ABOUT_STATS_HTML));
 
@@ -514,7 +514,7 @@ std::string AboutSync() {
                      full_status.max_consecutive_errors);
   }
 
-  static const StringPiece sync_html(
+  static const base::StringPiece sync_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
       IDR_ABOUT_SYNC_HTML));
 
@@ -720,7 +720,7 @@ void AboutMemoryHandler::OnDetailsAvailable() {
   }
 
   // Get about_memory.html
-  static const StringPiece memory_html(
+  static const base::StringPiece memory_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_ABOUT_MEMORY_HTML));
 
diff --git a/chrome/browser/browser_main.cc b/chrome/browser/browser_main.cc
index c2450f7..c15274b 100644
--- a/chrome/browser/browser_main.cc
+++ b/chrome/browser/browser_main.cc
@@ -192,9 +192,9 @@ base::LazyInstance<LazyDirectoryListerCacher> lazy_dir_lister(
     base::LINKER_INITIALIZED);
 
 // This is called indirectly by the network layer to access resources.
-StringPiece NetResourceProvider(int key) {
+base::StringPiece NetResourceProvider(int key) {
   if (IDR_DIR_HEADER_HTML == key)
-    return StringPiece(lazy_dir_lister.Pointer()->html_data);
+    return base::StringPiece(lazy_dir_lister.Pointer()->html_data);
 
   return ResourceBundle::GetSharedInstance().GetRawDataResource(key);
 }
diff --git a/chrome/browser/dom_ui/dom_ui_theme_source.cc b/chrome/browser/dom_ui/dom_ui_theme_source.cc
index f2ebbf5..bcdc813 100644
--- a/chrome/browser/dom_ui/dom_ui_theme_source.cc
+++ b/chrome/browser/dom_ui/dom_ui_theme_source.cc
@@ -181,7 +181,7 @@ void DOMUIThemeSource::InitNewTabCSS() {
   subst2.push_back(SkColorToRGBAString(color_section_link_underline));  // $$7
 
   // Get our template.
-  static const StringPiece new_tab_theme_css(
+  static const base::StringPiece new_tab_theme_css(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
       IDR_NEW_TAB_THEME_CSS));
 
@@ -215,7 +215,7 @@ void DOMUIThemeSource::InitNewIncognitoTabCSS() {
   subst.push_back(UTF8ToUTF16(GetNewTabBackgroundTilingCSS()));  // $5
 
   // Get our template.
-  static const StringPiece new_tab_theme_css(
+  static const base::StringPiece new_tab_theme_css(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
       IDR_NEW_INCOGNITO_TAB_THEME_CSS));
 
diff --git a/chrome/browser/dom_ui/downloads_ui.cc b/chrome/browser/dom_ui/downloads_ui.cc
index deb5ef1..52a26df 100644
--- a/chrome/browser/dom_ui/downloads_ui.cc
+++ b/chrome/browser/dom_ui/downloads_ui.cc
@@ -99,7 +99,7 @@ void DownloadsUIHTMLSource::StartDataRequest(const std::string& path,
 
   SetFontAndTextDirection(&localized_strings);
 
-  static const StringPiece downloads_html(
+  static const base::StringPiece downloads_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_DOWNLOADS_HTML));
   const std::string full_html = jstemplate_builder::GetI18nTemplateHtml(
diff --git a/chrome/browser/dom_ui/history_ui.cc b/chrome/browser/dom_ui/history_ui.cc
index c3eb8ad..45a994b 100644
--- a/chrome/browser/dom_ui/history_ui.cc
+++ b/chrome/browser/dom_ui/history_ui.cc
@@ -79,7 +79,7 @@ void HistoryUIHTMLSource::StartDataRequest(const std::string& path,
 
   SetFontAndTextDirection(&localized_strings);
 
-  static const StringPiece history_html(
+  static const base::StringPiece history_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_HISTORY_HTML));
   const std::string full_html = jstemplate_builder::GetI18nTemplateHtml(
diff --git a/chrome/browser/dom_ui/new_tab_ui.cc b/chrome/browser/dom_ui/new_tab_ui.cc
index 4f5bada..93fc8cb 100644
--- a/chrome/browser/dom_ui/new_tab_ui.cc
+++ b/chrome/browser/dom_ui/new_tab_ui.cc
@@ -421,12 +421,12 @@ void NewTabHTMLSource::InitFullHTML() {
   // In case we have the new new tab page enabled we first try to read the file
   // provided on the command line. If that fails we just get the resource from
   // the resource bundle.
-  StringPiece new_tab_html;
+  base::StringPiece new_tab_html;
   std::string new_tab_html_str;
   new_tab_html_str = GetCustomNewTabPageFromCommandLine();
 
   if (!new_tab_html_str.empty()) {
-    new_tab_html = StringPiece(new_tab_html_str);
+    new_tab_html = base::StringPiece(new_tab_html_str);
   }
 
   if (new_tab_html.empty()) {
@@ -510,7 +510,7 @@ void IncognitoTabHTMLSource::InitFullHTML() {
 
   SetFontAndTextDirection(&localized_strings);
 
-  static const StringPiece incognito_tab_html(
+  static const base::StringPiece incognito_tab_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_INCOGNITO_TAB_HTML));
 
diff --git a/chrome/browser/dom_ui/print_ui.cc b/chrome/browser/dom_ui/print_ui.cc
index 574abda..56514f9a 100644
--- a/chrome/browser/dom_ui/print_ui.cc
+++ b/chrome/browser/dom_ui/print_ui.cc
@@ -51,7 +51,7 @@ void PrintUIHTMLSource::StartDataRequest(const std::string& path,
   SetFontAndTextDirection(&localized_strings);
 
   // Setup the print html page.
-  static const StringPiece print_html(
+  static const base::StringPiece print_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_PRINT_TAB_HTML));
   const std::string full_html = jstemplate_builder::GetI18nTemplateHtml(
diff --git a/chrome/browser/extensions/extension_host.cc b/chrome/browser/extensions/extension_host.cc
index 168e002..39de133 100644
--- a/chrome/browser/extensions/extension_host.cc
+++ b/chrome/browser/extensions/extension_host.cc
@@ -151,7 +151,7 @@ void ExtensionHost::DidNavigate(RenderViewHost* render_view_host,
 }
 
 void ExtensionHost::DidStopLoading(RenderViewHost* render_view_host) {
-  static const StringPiece toolstrip_css(
+  static const base::StringPiece toolstrip_css(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_EXTENSIONS_TOOLSTRIP_CSS));
 #if defined(TOOLKIT_VIEWS)
diff --git a/chrome/browser/extensions/extensions_ui.cc b/chrome/browser/extensions/extensions_ui.cc
index 708b7e6..db10a9a 100644
--- a/chrome/browser/extensions/extensions_ui.cc
+++ b/chrome/browser/extensions/extensions_ui.cc
@@ -48,7 +48,7 @@ void ExtensionsUIHTMLSource::StartDataRequest(const std::string& path,
   localized_strings.SetString(L"title",
       l10n_util::GetString(IDS_EXTENSIONS_TITLE));
 
-  static const StringPiece extensions_html(
+  static const base::StringPiece extensions_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_EXTENSIONS_UI_HTML));
   std::string full_html(extensions_html.data(), extensions_html.size());
diff --git a/chrome/browser/extensions/external_pref_extension_provider.cc b/chrome/browser/extensions/external_pref_extension_provider.cc
index 7b371ed..e0f491f 100644
--- a/chrome/browser/extensions/external_pref_extension_provider.cc
+++ b/chrome/browser/extensions/external_pref_extension_provider.cc
@@ -58,7 +58,8 @@ void ExternalPrefExtensionProvider::VisitRegisteredExtension(
       continue;
     }
 
-    if (external_crx.find(FilePath::kParentDirectory) != StringPiece::npos) {
+    if (external_crx.find(FilePath::kParentDirectory) !=
+        base::StringPiece::npos) {
       LOG(WARNING) << "Path traversal not allowed in path: "
                    << external_crx.c_str();
       continue;
diff --git a/chrome/browser/extensions/user_script_master.cc b/chrome/browser/extensions/user_script_master.cc
index 7fa7832..b4130c8 100644
--- a/chrome/browser/extensions/user_script_master.cc
+++ b/chrome/browser/extensions/user_script_master.cc
@@ -23,8 +23,8 @@
 
 
 // Helper function to parse greasesmonkey headers
-static bool GetDeclarationValue(const StringPiece& line,
-                                const StringPiece& prefix,
+static bool GetDeclarationValue(const base::StringPiece& line,
+                                const base::StringPiece& prefix,
                                 std::string* value) {
   if (!line.starts_with(prefix))
     return false;
@@ -42,20 +42,20 @@ UserScriptMaster::ScriptReloader::ScriptReloader(UserScriptMaster* master)
 
 // static
 bool UserScriptMaster::ScriptReloader::ParseMetadataHeader(
-      const StringPiece& script_text, UserScript* script) {
+      const base::StringPiece& script_text, UserScript* script) {
   // http://wiki.greasespot.net/Metadata_block
-  StringPiece line;
+  base::StringPiece line;
   size_t line_start = 0;
   size_t line_end = 0;
   bool in_metadata = false;
 
-  static const StringPiece kUserScriptBegin("// ==UserScript==");
-  static const StringPiece kUserScriptEng("// ==/UserScript==");
-  static const StringPiece kIncludeDeclaration("// @include ");
-  static const StringPiece kMatchDeclaration("// @match ");
-  static const StringPiece kRunAtDeclaration("// @run-at ");
-  static const StringPiece kRunAtDocumentStartValue("document-start");
-  static const StringPiece kRunAtDocumentEndValue("document-end");
+  static const base::StringPiece kUserScriptBegin("// ==UserScript==");
+  static const base::StringPiece kUserScriptEng("// ==/UserScript==");
+  static const base::StringPiece kIncludeDeclaration("// @include ");
+  static const base::StringPiece kMatchDeclaration("// @match ");
+  static const base::StringPiece kRunAtDeclaration("// @run-at ");
+  static const base::StringPiece kRunAtDocumentStartValue("document-start");
+  static const base::StringPiece kRunAtDocumentEndValue("document-end");
 
   while (line_start < script_text.length()) {
     line_end = script_text.find('\n', line_start);
@@ -204,11 +204,11 @@ static base::SharedMemory* Serialize(const UserScriptList& scripts) {
     // Write scripts as 'data' so that we can read it out in the slave without
     // allocating a new string.
     for (size_t j = 0; j < script.js_scripts().size(); j++) {
-      StringPiece contents = script.js_scripts()[j].GetContent();
+      base::StringPiece contents = script.js_scripts()[j].GetContent();
       pickle.WriteData(contents.data(), contents.length());
     }
     for (size_t j = 0; j < script.css_scripts().size(); j++) {
-      StringPiece contents = script.css_scripts()[j].GetContent();
+      base::StringPiece contents = script.css_scripts()[j].GetContent();
       pickle.WriteData(contents.data(), contents.length());
     }
   }
diff --git a/chrome/browser/extensions/user_script_master.h b/chrome/browser/extensions/user_script_master.h
index 56aab84..af66879 100644
--- a/chrome/browser/extensions/user_script_master.h
+++ b/chrome/browser/extensions/user_script_master.h
@@ -16,7 +16,9 @@
 #include "testing/gtest/include/gtest/gtest_prod.h"
 
 class MessageLoop;
+namespace base {
 class StringPiece;
+}
 
 // Manages a segment of shared memory that contains the user scripts the user
 // has installed.  Lives on the UI thread.
@@ -70,7 +72,7 @@ class UserScriptMaster : public base::RefCounted<UserScriptMaster>,
       : public base::RefCounted<UserScriptMaster::ScriptReloader> {
    public:
     // Parses the includes out of |script| and returns them in |includes|.
-    static bool ParseMetadataHeader(const StringPiece& script_text,
+    static bool ParseMetadataHeader(const base::StringPiece& script_text,
                                     UserScript* script);
 
     static void LoadScriptsFromDirectory(const FilePath& script_dir,
diff --git a/chrome/browser/privacy_blacklist/blocked_response.cc b/chrome/browser/privacy_blacklist/blocked_response.cc
index aacb344..228886a 100644
--- a/chrome/browser/privacy_blacklist/blocked_response.cc
+++ b/chrome/browser/privacy_blacklist/blocked_response.cc
@@ -40,7 +40,7 @@ std::string GetHTML(const Blacklist::Match* match) {
   strings.SetString(L"name", entry->provider()->name());
   strings.SetString(L"url", entry->provider()->url());
 
-  const StringPiece html =
+  const base::StringPiece html =
     ResourceBundle::GetSharedInstance().GetRawDataResource(IDR_BLACKLIST_HTML);
   return jstemplate_builder::GetI18nTemplateHtml(html, &strings);
 }
diff --git a/chrome/browser/ssl/ssl_blocking_page.cc b/chrome/browser/ssl/ssl_blocking_page.cc
index a25fda3..d9fb4e6 100644
--- a/chrome/browser/ssl/ssl_blocking_page.cc
+++ b/chrome/browser/ssl/ssl_blocking_page.cc
@@ -81,7 +81,7 @@ std::string SSLBlockingPage::GetHTMLContents() {
       (l10n_util::GetTextDirection() == l10n_util::RIGHT_TO_LEFT) ?
        L"rtl" : L"ltr");
 
-  static const StringPiece html(
+  static const base::StringPiece html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_SSL_ROAD_BLOCK_HTML));
 
diff --git a/chrome/browser/ssl/ssl_policy.cc b/chrome/browser/ssl/ssl_policy.cc
index a5ecfdc..c8a6c7c 100644
--- a/chrome/browser/ssl/ssl_policy.cc
+++ b/chrome/browser/ssl/ssl_policy.cc
@@ -286,7 +286,7 @@ void SSLPolicy::ShowErrorPage(SSLCertErrorHandler* handler) {
       (l10n_util::GetTextDirection() == l10n_util::RIGHT_TO_LEFT) ?
       L"rtl" : L"ltr");
 
-  static const StringPiece html(
+  static const base::StringPiece html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_SSL_ERROR_HTML));
 
diff --git a/chrome/browser/views/sync/sync_setup_wizard.cc b/chrome/browser/views/sync/sync_setup_wizard.cc
index 0421e4e..3b187f7 100644
--- a/chrome/browser/views/sync/sync_setup_wizard.cc
+++ b/chrome/browser/views/sync/sync_setup_wizard.cc
@@ -49,15 +49,15 @@ void SyncResourcesSource::StartDataRequest(const std::string& path_raw,
 
   std::string response;
   if (path_raw == chrome::kSyncGaiaLoginPath) {
-    static const StringPiece html(ResourceBundle::GetSharedInstance()
+    static const base::StringPiece html(ResourceBundle::GetSharedInstance()
         .GetRawDataResource(IDR_GAIA_LOGIN_HTML));
     response = html.as_string();
   } else if (path_raw == chrome::kSyncMergeAndSyncPath) {
-    static const StringPiece html(ResourceBundle::GetSharedInstance()
+    static const base::StringPiece html(ResourceBundle::GetSharedInstance()
         .GetRawDataResource(IDR_MERGE_AND_SYNC_HTML));
     response = html.as_string();
   } else if (path_raw == chrome::kSyncSetupFlowPath) {
-    static const StringPiece html(ResourceBundle::GetSharedInstance()
+    static const base::StringPiece html(ResourceBundle::GetSharedInstance()
         .GetRawDataResource(IDR_SYNC_SETUP_FLOW_HTML));
     response = html.as_string();
   }
diff --git a/chrome/common/extensions/user_script.h b/chrome/common/extensions/user_script.h
index 7416472..4b571799 100644
--- a/chrome/common/extensions/user_script.h
+++ b/chrome/common/extensions/user_script.h
@@ -48,16 +48,16 @@ class UserScript {
 
     // If external_content_ is set returns it as content otherwise it returns
     // content_
-    const StringPiece GetContent() const {
+    const base::StringPiece GetContent() const {
       if (external_content_.data())
         return external_content_;
       else
         return content_;
     }
-    void set_external_content(const StringPiece& content) {
+    void set_external_content(const base::StringPiece& content) {
       external_content_ = content;
     }
-    const void set_content(const StringPiece& content) {
+    const void set_content(const base::StringPiece& content) {
       content_.assign(content.begin(), content.end());
     }
 
@@ -75,7 +75,7 @@ class UserScript {
 
     // The script content. It can be set to either loaded_content_ or
     // externally allocated string.
-    StringPiece external_content_;
+    base::StringPiece external_content_;
 
     // Set when the content is loaded by LoadContent
     std::string content_;
diff --git a/chrome/common/jstemplate_builder.cc b/chrome/common/jstemplate_builder.cc
index bb3a78f..30a7ba9 100644
--- a/chrome/common/jstemplate_builder.cc
+++ b/chrome/common/jstemplate_builder.cc
@@ -16,9 +16,9 @@
 
 namespace jstemplate_builder {
 
-std::string GetTemplateHtml(const StringPiece& html_template,
+std::string GetTemplateHtml(const base::StringPiece& html_template,
                             const DictionaryValue* json,
-                            const StringPiece& template_id) {
+                            const base::StringPiece& template_id) {
   std::string output(html_template.data(), html_template.size());
   AppendJsonHtml(json, &output);
   AppendJsTemplateSourceHtml(&output);
@@ -26,7 +26,7 @@ std::string GetTemplateHtml(const StringPiece& html_template,
   return output;
 }
 
-std::string GetI18nTemplateHtml(const StringPiece& html_template,
+std::string GetI18nTemplateHtml(const base::StringPiece& html_template,
                                 const DictionaryValue* json) {
   std::string output(html_template.data(), html_template.size());
   AppendJsonHtml(json, &output);
@@ -35,9 +35,9 @@ std::string GetI18nTemplateHtml(const StringPiece& html_template,
   return output;
 }
 
-std::string GetTemplatesHtml(const StringPiece& html_template,
+std::string GetTemplatesHtml(const base::StringPiece& html_template,
                              const DictionaryValue* json,
-                             const StringPiece& template_id) {
+                             const base::StringPiece& template_id) {
   std::string output(html_template.data(), html_template.size());
   AppendI18nTemplateSourceHtml(&output);
   AppendJsTemplateSourceHtml(&output);
@@ -67,8 +67,9 @@ void AppendJsonHtml(const DictionaryValue* json, std::string* output) {
 
 void AppendJsTemplateSourceHtml(std::string* output) {
   // fetch and cache the pointer of the jstemplate resource source text.
-  static const StringPiece jstemplate_src(ResourceBundle::GetSharedInstance().
-      GetRawDataResource(IDR_JSTEMPLATE_JS));
+  static const base::StringPiece jstemplate_src(
+      ResourceBundle::GetSharedInstance().GetRawDataResource(
+          IDR_JSTEMPLATE_JS));
 
   if (jstemplate_src.empty()) {
     NOTREACHED() << "Unable to get jstemplate src";
@@ -80,7 +81,7 @@ void AppendJsTemplateSourceHtml(std::string* output) {
   output->append("</script>");
 }
 
-void AppendJsTemplateProcessHtml(const StringPiece& template_id,
+void AppendJsTemplateProcessHtml(const base::StringPiece& template_id,
                                  std::string* output) {
   output->append("<script>");
   output->append("var tp = document.getElementById('");
@@ -92,7 +93,7 @@ void AppendJsTemplateProcessHtml(const StringPiece& template_id,
 
 void AppendI18nTemplateSourceHtml(std::string* output) {
   // fetch and cache the pointer of the jstemplate resource source text.
-  static const StringPiece i18n_template_src(
+  static const base::StringPiece i18n_template_src(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_I18N_TEMPLATE_JS));
 
diff --git a/chrome/common/jstemplate_builder.h b/chrome/common/jstemplate_builder.h
index e1861d2..ac8285f 100644
--- a/chrome/common/jstemplate_builder.h
+++ b/chrome/common/jstemplate_builder.h
@@ -16,29 +16,31 @@
 #include <string>
 
 class DictionaryValue;
+namespace base {
 class StringPiece;
+}
 
 namespace jstemplate_builder {
 
 // A helper function that generates a string of HTML to be loaded.  The
 // string includes the HTML and the javascript code necessary to generate the
 // full page with support for JsTemplates.
-std::string GetTemplateHtml(const StringPiece& html_template,
+std::string GetTemplateHtml(const base::StringPiece& html_template,
                             const DictionaryValue* json,
-                            const StringPiece& template_id);
+                            const base::StringPiece& template_id);
 
 // A helper function that generates a string of HTML to be loaded.  The
 // string includes the HTML and the javascript code necessary to generate the
 // full page with support for i18n Templates.
-std::string GetI18nTemplateHtml(const StringPiece& html_template,
+std::string GetI18nTemplateHtml(const base::StringPiece& html_template,
                                 const DictionaryValue* json);
 
 // A helper function that generates a string of HTML to be loaded.  The
 // string includes the HTML and the javascript code necessary to generate the
 // full page with support for both i18n Templates and JsTemplates.
-std::string GetTemplatesHtml(const StringPiece& html_template,
+std::string GetTemplatesHtml(const base::StringPiece& html_template,
                              const DictionaryValue* json,
-                             const StringPiece& template_id);
+                             const base::StringPiece& template_id);
 
 // The following functions build up the different parts that the above
 // templates use.
@@ -52,7 +54,7 @@ void AppendJsTemplateSourceHtml(std::string* output);
 
 // Appends the code that processes the JsTemplate with the JSON. You should
 // call AppendJsTemplateSourceHtml and AppendJsonHtml before calling this.
-void AppendJsTemplateProcessHtml(const StringPiece& template_id,
+void AppendJsTemplateProcessHtml(const base::StringPiece& template_id,
                                  std::string* output);
 
 // Appends the source for i18n Templates in a script tag.
diff --git a/chrome/renderer/render_view.cc b/chrome/renderer/render_view.cc
index cb4f6e7..31739d3 100644
--- a/chrome/renderer/render_view.cc
+++ b/chrome/renderer/render_view.cc
@@ -3129,7 +3129,7 @@ bool RenderView::MaybeLoadAlternateErrorPage(WebFrame* frame,
 
 std::string RenderView::GetAltHTMLForTemplate(
     const DictionaryValue& error_strings, int template_resource_id) const {
-  const StringPiece template_html(
+  const base::StringPiece template_html(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           template_resource_id));
 
diff --git a/chrome/renderer/renderer_glue.cc b/chrome/renderer/renderer_glue.cc
index 2597264..c992010 100644
--- a/chrome/renderer/renderer_glue.cc
+++ b/chrome/renderer/renderer_glue.cc
@@ -158,7 +158,7 @@ void AppendToLog(const char* file, int line, const char* msg) {
   logging::LogMessage(file, line).stream() << msg;
 }
 
-StringPiece GetDataResource(int resource_id) {
+base::StringPiece GetDataResource(int resource_id) {
   return ResourceBundle::GetSharedInstance().GetRawDataResource(resource_id);
 }
 
diff --git a/chrome/renderer/user_script_slave.cc b/chrome/renderer/user_script_slave.cc
index 07e8746..2ebd68f 100644
--- a/chrome/renderer/user_script_slave.cc
+++ b/chrome/renderer/user_script_slave.cc
@@ -42,8 +42,8 @@ UserScriptSlave::UserScriptSlave()
                 IDR_GREASEMONKEY_API_JS);
 
   // Count the number of lines that will be injected before the user script.
-  StringPiece::size_type pos = 0;
-  while ((pos = api_js_.find('\n', pos)) != StringPiece::npos) {
+  base::StringPiece::size_type pos = 0;
+  while ((pos = api_js_.find('\n', pos)) != base::StringPiece::npos) {
     user_script_start_line_++;
     pos++;
   }
@@ -95,14 +95,14 @@ bool UserScriptSlave::UpdateScripts(base::SharedMemoryHandle shared_memory) {
       int body_length = 0;
       CHECK(pickle.ReadData(&iter, &body, &body_length));
       script->js_scripts()[j].set_external_content(
-          StringPiece(body, body_length));
+          base::StringPiece(body, body_length));
     }
     for (size_t j = 0; j < script->css_scripts().size(); ++j) {
       const char* body = NULL;
       int body_length = 0;
       CHECK(pickle.ReadData(&iter, &body, &body_length));
       script->css_scripts()[j].set_external_content(
-          StringPiece(body, body_length));
+          base::StringPiece(body, body_length));
     }
   }
 
diff --git a/chrome/renderer/user_script_slave.h b/chrome/renderer/user_script_slave.h
index 8f1fc9b..614dd85 100644
--- a/chrome/renderer/user_script_slave.h
+++ b/chrome/renderer/user_script_slave.h
@@ -40,7 +40,7 @@ class UserScriptSlave {
   STLElementDeleter<std::vector<UserScript*> > script_deleter_;
 
   // Greasemonkey API source that is injected with the scripts.
-  StringPiece api_js_;
+  base::StringPiece api_js_;
 
   // The line number of the first line of the user script among all of the
   // injected javascript.  This is used to make reported errors correspond with
diff --git a/chrome/test/v8_unit_test.cc b/chrome/test/v8_unit_test.cc
index 43db5f1..4b94ad9 100644
--- a/chrome/test/v8_unit_test.cc
+++ b/chrome/test/v8_unit_test.cc
@@ -14,8 +14,8 @@ void V8UnitTest::SetUp() {
   context_ = v8::Context::New(NULL, global);
 }
 
-void V8UnitTest::ExecuteScriptInContext(const StringPiece& script_source,
-                                        const StringPiece& script_name) {
+void V8UnitTest::ExecuteScriptInContext(const base::StringPiece& script_source,
+                                        const base::StringPiece& script_name) {
   v8::Context::Scope context_scope(context_);
   v8::HandleScope handle_scope;
   v8::Handle<v8::String> source = v8::String::New(script_source.data(),
diff --git a/chrome/test/v8_unit_test.h b/chrome/test/v8_unit_test.h
index 1502e9d..644c660 100644
--- a/chrome/test/v8_unit_test.h
+++ b/chrome/test/v8_unit_test.h
@@ -10,7 +10,9 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include "v8/include/v8.h"
 
+namespace base {
 class StringPiece;
+}
 
 // A superclass for unit tests that involve running JavaScript.  This class
 // sets up V8 context and has methods that make it easy to execute scripts in
@@ -23,8 +25,8 @@ class V8UnitTest : public testing::Test {
  protected:
   // Executes the given script source in the context.  The specified script
   // name is used when reporting errors.
-  virtual void ExecuteScriptInContext(const StringPiece& script_source,
-                                      const StringPiece& script_name);
+  virtual void ExecuteScriptInContext(const base::StringPiece& script_source,
+                                      const base::StringPiece& script_name);
 
   // Converts a v8::TryCatch into a human readable string.
   virtual std::string ExceptionToString(v8::TryCatch* try_catch);
diff --git a/chrome/tools/mac_helpers/infoplist_strings_util.mm b/chrome/tools/mac_helpers/infoplist_strings_util.mm
index f2bbf7a..fbdc924 100644
--- a/chrome/tools/mac_helpers/infoplist_strings_util.mm
+++ b/chrome/tools/mac_helpers/infoplist_strings_util.mm
@@ -76,7 +76,7 @@ NSString* LoadStringFromDataPack(base::DataPack* data_pack,
                                  uint32_t resource_id,
                                  const char* resource_id_str) {
   NSString* result = nil;
-  StringPiece data;
+  base::StringPiece data;
   if (data_pack->Get(resource_id, &data)) {
     // Data pack encodes strings as UTF16.
     result =
diff --git a/net/base/net_module.cc b/net/base/net_module.cc
index de9a586..d7f1918 100644
--- a/net/base/net_module.cc
+++ b/net/base/net_module.cc
@@ -14,8 +14,8 @@ void NetModule::SetResourceProvider(ResourceProvider func) {
 }
 
 // static
-StringPiece NetModule::GetResource(int key) {
-  return resource_provider ? resource_provider(key) : StringPiece();
+base::StringPiece NetModule::GetResource(int key) {
+  return resource_provider ? resource_provider(key) : base::StringPiece();
 }
 
 }  // namespace net
diff --git a/net/base/net_module.h b/net/base/net_module.h
index 06404d0..6df4bfe 100644
--- a/net/base/net_module.h
+++ b/net/base/net_module.h
@@ -19,7 +19,7 @@ namespace net {
 //
 class NetModule {
  public:
-  typedef StringPiece (*ResourceProvider)(int key);
+  typedef base::StringPiece (*ResourceProvider)(int key);
 
   // Set the function to call when the net module needs resources
   static void SetResourceProvider(ResourceProvider func);
@@ -27,7 +27,7 @@ class NetModule {
   // Call the resource provider (if one exists) to get the specified resource.
   // Returns an empty string if the resource does not exist or if there is no
   // resource provider.
-  static StringPiece GetResource(int key);
+  static base::StringPiece GetResource(int key);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(NetModule);
diff --git a/net/base/net_util.cc b/net/base/net_util.cc
index 13e99a5..5f6b548 100644
--- a/net/base/net_util.cc
+++ b/net/base/net_util.cc
@@ -918,7 +918,8 @@ std::string CanonicalizeHost(const std::wstring& host,
 }
 
 std::string GetDirectoryListingHeader(const string16& title) {
-  static const StringPiece header(NetModule::GetResource(IDR_DIR_HEADER_HTML));
+  static const base::StringPiece header(
+      NetModule::GetResource(IDR_DIR_HEADER_HTML));
   // This can be null in unit tests.
   DLOG_IF(WARNING, header.empty()) <<
       "Missing resource: directory listing header";
diff --git a/net/base/registry_controlled_domain.cc b/net/base/registry_controlled_domain.cc
index 2bcfba5..40dea62 100644
--- a/net/base/registry_controlled_domain.cc
+++ b/net/base/registry_controlled_domain.cc
@@ -276,21 +276,23 @@ void RegistryControlledDomainService::Init() {
   ParseDomainData(kDomainData);
 }
 
-void RegistryControlledDomainService::ParseDomainData(const StringPiece& data) {
+void RegistryControlledDomainService::ParseDomainData(
+    const base::StringPiece& data) {
   domain_set_.clear();
 
   size_t line_end = 0;
   size_t line_start = 0;
   while (line_start < data.size()) {
     line_end = data.find('\n', line_start);
-    if (line_end == StringPiece::npos)
+    if (line_end == base::StringPiece::npos)
       line_end = data.size();
-    AddRule(StringPiece(data.data() + line_start, line_end - line_start));
+    AddRule(base::StringPiece(data.data() + line_start, line_end - line_start));
     line_start = line_end + 1;
   }
 }
 
-void RegistryControlledDomainService::AddRule(const StringPiece& rule_str) {
+void RegistryControlledDomainService::AddRule(
+    const base::StringPiece& rule_str) {
   DomainEntry rule(rule_str.data(), rule_str.size());
 
   // Valid rules may be either wild or exceptions, but not both.
diff --git a/net/base/registry_controlled_domain.h b/net/base/registry_controlled_domain.h
index 2c6edb7..1897e8b5 100644
--- a/net/base/registry_controlled_domain.h
+++ b/net/base/registry_controlled_domain.h
@@ -227,7 +227,7 @@ class RegistryControlledDomainService {
   // consider the attributes when doing comparisons, so as far as any data
   // structures our concerned (ex our set), two DomainEntry's are equal as long
   // as their StringPiece (the domain) is equal.  This is the behavior we want.
-  class DomainEntry : public StringPiece {
+  class DomainEntry : public base::StringPiece {
    public:
     struct DomainEntryAttributes {
       DomainEntryAttributes() : exception(false), wildcard(false) { }
@@ -242,8 +242,9 @@ class RegistryControlledDomainService {
       bool wildcard;
     };
 
-    DomainEntry() : StringPiece() { }
-    DomainEntry(const char* ptr, size_type size) : StringPiece(ptr, size) { }
+    DomainEntry() : base::StringPiece() { }
+    DomainEntry(const char* ptr, size_type size)
+        : base::StringPiece(ptr, size) { }
     ~DomainEntry() { }
 
     // We override StringPiece's operator < to make it more efficent, since we
@@ -252,7 +253,7 @@ class RegistryControlledDomainService {
     bool operator<(const DomainEntry& other) const {
       // If we are the same size, call up to StringPiece's real less than.
       if (size() == other.size())
-        return *static_cast<const StringPiece*>(this) < other;
+        return *static_cast<const base::StringPiece*>(this) < other;
       // Consider ourselves less if we are smaller
       return size() < other.size();
     }
@@ -269,7 +270,7 @@ class RegistryControlledDomainService {
   // were populated from an embedded resource, we will reference the embedded
   // resource directly.  If we were populated through UseDomainData, then our
   // StringPiece will reference our local copy in copied_domain_data_.
-  void ParseDomainData(const StringPiece& data);
+  void ParseDomainData(const base::StringPiece& data);
 
   // Returns the singleton instance, after attempting to initialize it.
   // NOTE that if the effective-TLD data resource can't be found, the instance
@@ -277,7 +278,7 @@ class RegistryControlledDomainService {
   static RegistryControlledDomainService* GetInstance();
 
   // Adds one rule, assumed to be valid, to the domain_set_.
-  void AddRule(const StringPiece& rule_str);
+  void AddRule(const base::StringPiece& rule_str);
 
   // Internal workings of the static public methods.  See above.
   static std::string GetDomainAndRegistryImpl(const std::string& host);
diff --git a/net/http/http_chunked_decoder.cc b/net/http/http_chunked_decoder.cc
index 71f7554..25b789f 100644
--- a/net/http/http_chunked_decoder.cc
+++ b/net/http/http_chunked_decoder.cc
@@ -93,8 +93,8 @@ int HttpChunkedDecoder::ScanForChunkRemaining(const char* buf, int buf_len) {
 
   int bytes_consumed = 0;
 
-  size_t index_of_lf = StringPiece(buf, buf_len).find('\n');
-  if (index_of_lf != StringPiece::npos) {
+  size_t index_of_lf = base::StringPiece(buf, buf_len).find('\n');
+  if (index_of_lf != base::StringPiece::npos) {
     buf_len = static_cast<int>(index_of_lf);
     if (buf_len && buf[buf_len - 1] == '\r')  // Eliminate a preceding CR.
       buf_len--;
@@ -121,8 +121,8 @@ int HttpChunkedDecoder::ScanForChunkRemaining(const char* buf, int buf_len) {
        chunk_terminator_remaining_ = false;
     } else if (buf_len) {
       // Ignore any chunk-extensions.
-      size_t index_of_semicolon = StringPiece(buf, buf_len).find(';');
-      if (index_of_semicolon != StringPiece::npos)
+      size_t index_of_semicolon = base::StringPiece(buf, buf_len).find(';');
+      if (index_of_semicolon != base::StringPiece::npos)
         buf_len = static_cast<int>(index_of_semicolon);
 
       if (!ParseChunkSize(buf, buf_len, &chunk_remaining_)) {
@@ -181,8 +181,8 @@ bool HttpChunkedDecoder::ParseChunkSize(const char* start, int len, int* out) {
 
   // Be more restrictive than HexStringToInt;
   // don't allow inputs with leading "-", "+", "0x", "0X"
-  if (StringPiece(start, len).find_first_not_of("0123456789abcdefABCDEF")!=
-      StringPiece::npos)
+  if (base::StringPiece(start, len).find_first_not_of("0123456789abcdefABCDEF")
+      != base::StringPiece::npos)
     return false;
 
   int parsed_number;
diff --git a/net/http/http_util.cc b/net/http/http_util.cc
index 4381117..41aa554 100644
--- a/net/http/http_util.cc
+++ b/net/http/http_util.cc
@@ -500,8 +500,8 @@ static bool IsLineSegmentContinuable(const char* begin, const char* end) {
 
 // Helper used by AssembleRawHeaders, to find the end of the status line.
 static const char* FindStatusLineEnd(const char* begin, const char* end) {
-  size_t i = StringPiece(begin, end - begin).find_first_of("\r\n");
-  if (i == StringPiece::npos)
+  size_t i = base::StringPiece(begin, end - begin).find_first_of("\r\n");
+  if (i == base::StringPiece::npos)
     return end;
   return begin + i;
 }
diff --git a/net/url_request/url_request_unittest.cc b/net/url_request/url_request_unittest.cc
index 2f2f2e1..d82e085 100644
--- a/net/url_request/url_request_unittest.cc
+++ b/net/url_request/url_request_unittest.cc
@@ -78,7 +78,7 @@ class TestURLRequest : public URLRequest {
   }
 };
 
-StringPiece TestNetResourceProvider(int key) {
+base::StringPiece TestNetResourceProvider(int key) {
   return "header";
 }
 
diff --git a/webkit/glue/devtools/debugger_agent_impl.cc b/webkit/glue/devtools/debugger_agent_impl.cc
index 70353ae..45b5470 100644
--- a/webkit/glue/devtools/debugger_agent_impl.cc
+++ b/webkit/glue/devtools/debugger_agent_impl.cc
@@ -132,18 +132,19 @@ void DebuggerAgentImpl::CreateUtilityContext(
   global->Set(v8::String::New("contentWindow"), window_global);
 
   // Inject javascript into the context.
-  StringPiece basejs = webkit_glue::GetDataResource(IDR_DEVTOOLS_BASE_JS);
+  base::StringPiece basejs = webkit_glue::GetDataResource(IDR_DEVTOOLS_BASE_JS);
   v8::Script::Compile(v8::String::New(basejs.as_string().c_str()))->Run();
 
-  StringPiece injectjs_webkit =
+  base::StringPiece injectjs_webkit =
       webkit_glue::GetDataResource(IDR_DEVTOOLS_INJECT_WEBKIT_JS);
   v8::Script::Compile(
       v8::String::New(injectjs_webkit.as_string().c_str()))->Run();
 
-  StringPiece injectjs = webkit_glue::GetDataResource(IDR_DEVTOOLS_INJECT_JS);
+  base::StringPiece injectjs = webkit_glue::GetDataResource(
+      IDR_DEVTOOLS_INJECT_JS);
   v8::Script::Compile(v8::String::New(injectjs.as_string().c_str()))->Run();
 
-  StringPiece inject_dispatchjs = webkit_glue::GetDataResource(
+  base::StringPiece inject_dispatchjs = webkit_glue::GetDataResource(
       IDR_DEVTOOLS_INJECT_DISPATCH_JS);
   v8::Script::Compile(v8::String::New(
       inject_dispatchjs.as_string().c_str()))->Run();
diff --git a/webkit/glue/webkit_glue.h b/webkit/glue/webkit_glue.h
index 302f047..eab53a4 100644
--- a/webkit/glue/webkit_glue.h
+++ b/webkit/glue/webkit_glue.h
@@ -21,10 +21,13 @@
 
 class GURL;
 class SkBitmap;
-class StringPiece;
 class WebView;
 struct WebPluginInfo;
 
+namespace base {
+class StringPiece;
+}
+
 namespace skia {
 class PlatformCanvas;
 }
@@ -139,7 +142,7 @@ string16 GetLocalizedString(int message_id);
 
 // Returns the raw data for a resource.  This resource must have been
 // specified as BINDATA in the relevant .rc file.
-StringPiece GetDataResource(int resource_id);
+base::StringPiece GetDataResource(int resource_id);
 
 #if defined(OS_WIN)
 // Loads and returns a cursor.
diff --git a/webkit/glue/webkitclient_impl.cc b/webkit/glue/webkitclient_impl.cc
index b4acce3..ddd213d 100644
--- a/webkit/glue/webkitclient_impl.cc
+++ b/webkit/glue/webkitclient_impl.cc
@@ -185,7 +185,7 @@ WebData WebKitClientImpl::loadResource(const char* name) {
   };
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(resources); ++i) {
     if (!strcmp(name, resources[i].name)) {
-      StringPiece resource = GetDataResource(resources[i].id);
+      base::StringPiece resource = GetDataResource(resources[i].id);
       return WebData(resource.data(), resource.size());
     }
   }
diff --git a/webkit/tools/test_shell/test_shell.h b/webkit/tools/test_shell/test_shell.h
index b99cbea..5d14c55 100644
--- a/webkit/tools/test_shell/test_shell.h
+++ b/webkit/tools/test_shell/test_shell.h
@@ -47,10 +47,13 @@
 typedef std::list<gfx::NativeWindow> WindowList;
 
 struct WebPreferences;
-class StringPiece;
 class TestNavigationEntry;
 class TestNavigationController;
 
+namespace base {
+class StringPiece;
+}
+
 class TestShell {
 public:
     struct TestParams {
@@ -268,7 +271,7 @@ public:
     static void ShowStartupDebuggingDialog();
 
     // This is called indirectly by the network layer to access resources.
-    static StringPiece NetResourceProvider(int key);
+    static base::StringPiece NetResourceProvider(int key);
 
 protected:
     bool Initialize(const GURL& starting_url);
diff --git a/webkit/tools/test_shell/test_shell_gtk.cc b/webkit/tools/test_shell/test_shell_gtk.cc
index 87e80a5..848751d 100644
--- a/webkit/tools/test_shell/test_shell_gtk.cc
+++ b/webkit/tools/test_shell/test_shell_gtk.cc
@@ -181,7 +181,7 @@ void TestShell::InitializeTestShell(bool layout_test_mode) {
 
   // fontconfig only knows how to load font config configs from a file name, so
   // we write to a temp file.
-  StringPiece font_config_xml;
+  base::StringPiece font_config_xml;
   g_resource_data_pack->Get(IDR_LINUX_FONT_CONFIG, &font_config_xml);
   FilePath fontconfig_path;
   if (!file_util::CreateTemporaryFile(&fontconfig_path)) {
@@ -270,7 +270,7 @@ void TestShell::InitializeTestShell(bool layout_test_mode) {
   }
 
   // Also load the layout-test-specific "Ahem" font.
-  StringPiece ahem_font;
+  base::StringPiece ahem_font;
   g_resource_data_pack->Get(IDR_AHEM_FONT, &ahem_font);
   g_ahem_path = new FilePath;
   if (!file_util::CreateTemporaryFile(g_ahem_path)) {
@@ -632,8 +632,8 @@ void TestShell::ShowStartupDebuggingDialog() {
 }
 
 // static
-StringPiece TestShell::NetResourceProvider(int key) {
-  StringPiece res;
+base::StringPiece TestShell::NetResourceProvider(int key) {
+  base::StringPiece res;
   g_resource_data_pack->Get(key, &res);
   return res;
 }
@@ -643,7 +643,7 @@ StringPiece TestShell::NetResourceProvider(int key) {
 namespace webkit_glue {
 
 string16 GetLocalizedString(int message_id) {
-  StringPiece res;
+  base::StringPiece res;
   if (!g_resource_data_pack->Get(message_id, &res)) {
     LOG(FATAL) << "failed to load webkit string with id " << message_id;
   }
@@ -652,7 +652,7 @@ string16 GetLocalizedString(int message_id) {
                   res.length() / 2);
 }
 
-StringPiece GetDataResource(int resource_id) {
+base::StringPiece GetDataResource(int resource_id) {
   switch (resource_id) {
     case IDR_FEED_PREVIEW:
       // It is necessary to return a feed preview template that contains
diff --git a/webkit/tools/test_shell/test_shell_mac.mm b/webkit/tools/test_shell/test_shell_mac.mm
index 5566380..299876a 100644
--- a/webkit/tools/test_shell/test_shell_mac.mm
+++ b/webkit/tools/test_shell/test_shell_mac.mm
@@ -609,9 +609,9 @@ void TestShell::ShowStartupDebuggingDialog() {
   [alert runModal];
 }
 
-StringPiece TestShell::NetResourceProvider(int key) {
+base::StringPiece TestShell::NetResourceProvider(int key) {
   // TODO(port): Return the requested resource.
-  return StringPiece();
+  return base::StringPiece();
 }
 
 //-----------------------------------------------------------------------------
@@ -619,7 +619,7 @@ StringPiece TestShell::NetResourceProvider(int key) {
 namespace webkit_glue {
 
 string16 GetLocalizedString(int message_id) {
-  StringPiece res;
+  base::StringPiece res;
   if (!g_resource_data_pack->Get(message_id, &res)) {
     LOG(FATAL) << "failed to load webkit string with id " << message_id;
   }
@@ -628,7 +628,7 @@ string16 GetLocalizedString(int message_id) {
                   res.length() / 2);
 }
 
-StringPiece GetDataResource(int resource_id) {
+base::StringPiece GetDataResource(int resource_id) {
   switch (resource_id) {
   case IDR_BROKENIMAGE: {
     // Use webkit's broken image icon (16x16)
@@ -678,7 +678,7 @@ StringPiece GetDataResource(int resource_id) {
     break;
   }
 
-  return StringPiece();
+  return base::StringPiece();
 }
 
 void GetPlugins(bool refresh, std::vector<WebPluginInfo>* plugins) {
diff --git a/webkit/tools/test_shell/test_shell_win.cc b/webkit/tools/test_shell/test_shell_win.cc
index e097b25..2bde111 100644
--- a/webkit/tools/test_shell/test_shell_win.cc
+++ b/webkit/tools/test_shell/test_shell_win.cc
@@ -126,16 +126,17 @@ FilePath GetResourcesFilePath() {
   return path.AppendASCII("resources");
 }
 
-static StringPiece GetRawDataResource(HMODULE module, int resource_id) {
+static base::StringPiece GetRawDataResource(HMODULE module, int resource_id) {
   void* data_ptr;
   size_t data_size;
   return base::GetDataResourceFromModule(module, resource_id, &data_ptr,
-                                         &data_size) ?
-      StringPiece(static_cast<char*>(data_ptr), data_size) : StringPiece();
+                                         &data_size)
+      ? base::StringPiece(static_cast<char*>(data_ptr), data_size)
+      : base::StringPiece();
 }
 
 // This is called indirectly by the network layer to access resources.
-StringPiece NetResourceProvider(int key) {
+base::StringPiece NetResourceProvider(int key) {
   return GetRawDataResource(::GetModuleHandle(NULL), key);
 }
 
@@ -655,7 +656,7 @@ void TestShell::ShowStartupDebuggingDialog() {
 }
 
 // static
-StringPiece TestShell::NetResourceProvider(int key) {
+base::StringPiece TestShell::NetResourceProvider(int key) {
   return GetRawDataResource(::GetModuleHandle(NULL), key);
 }
 
@@ -677,7 +678,7 @@ string16 GetLocalizedString(int message_id) {
 }
 
 // TODO(tc): Convert this to using resources from test_shell.rc.
-StringPiece GetDataResource(int resource_id) {
+base::StringPiece GetDataResource(int resource_id) {
   switch (resource_id) {
   case IDR_BROKENIMAGE: {
     // Use webkit's broken image icon (16x16)
@@ -730,7 +731,7 @@ StringPiece GetDataResource(int resource_id) {
     break;
   }
 
-  return StringPiece();
+  return base::StringPiece();
 }
 
 HCURSOR LoadCursor(int cursor_id) {
diff --git a/webkit/tools/test_shell/test_worker/test_worker_main.cc b/webkit/tools/test_shell/test_worker/test_worker_main.cc
index 1002fbe..94c966d 100644
--- a/webkit/tools/test_shell/test_worker/test_worker_main.cc
+++ b/webkit/tools/test_shell/test_worker/test_worker_main.cc
@@ -166,8 +166,8 @@ string16 GetLocalizedString(int message_id) {
   return EmptyString16();
 }
 
-StringPiece GetDataResource(int resource_id) {
-  return StringPiece();
+base::StringPiece GetDataResource(int resource_id) {
+  return base::StringPiece();
 }
 
 void SetMediaPlayerAvailable(bool value) {