JSON/IDL Compiler now generates event names as of r215660. Use these generated event names instead of custom constant strings.

BUG=268380

Review URL: https://chromiumcodereview.appspot.com/23013006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@218378 0039d316-1c4b-4281-b951-d872f2087c98

62 files changed, 537 insertions, 698 deletions

diff --git a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.cc b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.cc
index d9e03fb..f2e18eb 100644
--- a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.cc
+++ b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.cc
@@ -18,11 +18,12 @@
 
 namespace extensions {
 
+namespace activity_log_private = api::activity_log_private;
+
 using api::activity_log_private::ExtensionActivity;
 
 const char kActivityLogExtensionId[] = "acldcpdepobcjbdanifkmfndkjoilgba";
 const char kActivityLogTestExtensionId[] = "ajabfgledjhbabeoojlabelaifmakodf";
-const char kNewActivityEventName[] = "activityLogPrivate.onExtensionActivity";
 
 static base::LazyInstance<ProfileKeyedAPIFactory<ActivityLogAPI> >
     g_factory = LAZY_INSTANCE_INITIALIZER;
@@ -48,7 +49,7 @@ ActivityLogAPI::ActivityLogAPI(Profile* profile)
   activity_log_ = extensions::ActivityLog::GetInstance(profile_);
   DCHECK(activity_log_);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, kNewActivityEventName);
+      this, activity_log_private::OnExtensionActivity::kEventName);
   activity_log_->AddObserver(this);
   initialized_ = true;
 }
@@ -84,7 +85,9 @@ void ActivityLogAPI::OnExtensionActivity(scoped_refptr<Action> activity) {
   scoped_ptr<ExtensionActivity> activity_arg =
       activity->ConvertToExtensionActivity();
   value->Append(activity_arg->ToValue().release());
-  scoped_ptr<Event> event(new Event(kNewActivityEventName, value.Pass()));
+  scoped_ptr<Event> event(
+      new Event(activity_log_private::OnExtensionActivity::kEventName,
+          value.Pass()));
   event->restrict_to_profile = profile_;
   ExtensionSystem::Get(profile_)->event_router()->BroadcastEvent(event.Pass());
 }
diff --git a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
index ea74c1f..cab0ccf 100644
--- a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
+++ b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
@@ -24,7 +24,6 @@ class ActivityLog;
 // The ID of the trusted/whitelisted ActivityLog extension.
 extern const char kActivityLogExtensionId[];
 extern const char kActivityLogTestExtensionId[];
-extern const char kNewActivityEventName[];
 
 // Handles interactions between the Activity Log API and implementation.
 class ActivityLogAPI : public ProfileKeyedAPI,
diff --git a/chrome/browser/extensions/api/alarms/alarm_manager.cc b/chrome/browser/extensions/api/alarms/alarm_manager.cc
index aa483ee..188fa3b 100644
--- a/chrome/browser/extensions/api/alarms/alarm_manager.cc
+++ b/chrome/browser/extensions/api/alarms/alarm_manager.cc
@@ -19,13 +19,14 @@
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/state_store.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/alarms.h"
 #include "content/public/browser/notification_service.h"
 
 namespace extensions {
 
-namespace {
+namespace alarms = api::alarms;
 
-const char kOnAlarmEvent[] = "alarms.onAlarm";
+namespace {
 
 // A list of alarms that this extension has set.
 const char kRegisteredAlarms[] = "alarms";
@@ -43,7 +44,8 @@ class DefaultAlarmDelegate : public AlarmManager::Delegate {
                        const Alarm& alarm) OVERRIDE {
     scoped_ptr<base::ListValue> args(new base::ListValue());
     args->Append(alarm.js_alarm->ToValue().release());
-    scoped_ptr<Event> event(new Event(kOnAlarmEvent, args.Pass()));
+    scoped_ptr<Event> event(new Event(alarms::OnAlarm::kEventName,
+                                      args.Pass()));
     ExtensionSystem::Get(profile_)->event_router()->DispatchEventToExtension(
         extension_id, event.Pass());
   }
diff --git a/chrome/browser/extensions/api/app_runtime/app_runtime_api.cc b/chrome/browser/extensions/api/app_runtime/app_runtime_api.cc
index 5b7bd40..b976dc7 100644
--- a/chrome/browser/extensions/api/app_runtime/app_runtime_api.cc
+++ b/chrome/browser/extensions/api/app_runtime/app_runtime_api.cc
@@ -10,27 +10,27 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/api/file_handlers/app_file_handler_util.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/app_runtime.h"
 #include "chrome/common/extensions/extension.h"
 #include "content/public/browser/web_contents.h"
 #include "url/gurl.h"
 
 namespace extensions {
 
-namespace {
+namespace app_runtime = api::app_runtime;
 
-using event_names::kOnLaunched;
-using event_names::kOnRestarted;
+namespace {
 
 void DispatchOnLaunchedEventImpl(const std::string& extension_id,
                                  scoped_ptr<base::ListValue> args,
                                  Profile* profile) {
   extensions::ExtensionSystem* system =
       extensions::ExtensionSystem::Get(profile);
-  scoped_ptr<Event> event(new Event(kOnLaunched, args.Pass()));
+  scoped_ptr<Event> event(new Event(app_runtime::OnLaunched::kEventName,
+                                    args.Pass()));
   event->restrict_to_profile = profile;
   system->event_router()->DispatchEventWithLazyListener(extension_id,
                                                         event.Pass());
@@ -49,7 +49,8 @@ void AppEventRouter::DispatchOnLaunchedEvent(
 void AppEventRouter::DispatchOnRestartedEvent(Profile* profile,
                                               const Extension* extension) {
   scoped_ptr<base::ListValue> arguments(new base::ListValue());
-  scoped_ptr<Event> event(new Event(kOnRestarted, arguments.Pass()));
+  scoped_ptr<Event> event(new Event(app_runtime::OnRestarted::kEventName,
+                                    arguments.Pass()));
   event->restrict_to_profile = profile;
   extensions::ExtensionSystem::Get(profile)->event_router()->
       DispatchEventToExtension(extension->id(), event.Pass());
diff --git a/chrome/browser/extensions/api/audio/audio_api.cc b/chrome/browser/extensions/api/audio/audio_api.cc
index b6c37fb..359b48d 100644
--- a/chrome/browser/extensions/api/audio/audio_api.cc
+++ b/chrome/browser/extensions/api/audio/audio_api.cc
@@ -6,12 +6,14 @@
 
 #include "base/lazy_instance.h"
 #include "base/values.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
+#include "chrome/common/extensions/api/audio.h"
 
 namespace extensions {
 
+namespace audio = api::audio;
+
 static base::LazyInstance<ProfileKeyedAPIFactory<AudioAPI> >
 g_factory = LAZY_INSTANCE_INITIALIZER;
 
@@ -39,7 +41,7 @@ AudioService* AudioAPI::GetService() const {
 void AudioAPI::OnDeviceChanged() {
   if (profile_ && ExtensionSystem::Get(profile_)->event_router()) {
     scoped_ptr<Event> event(new Event(
-        event_names::kOnAudioDeviceChanged,
+        audio::OnDeviceChanged::kEventName,
         scoped_ptr<base::ListValue>(new base::ListValue())));
     ExtensionSystem::Get(profile_)->event_router()->BroadcastEvent(
         event.Pass());
diff --git a/chrome/browser/extensions/api/bluetooth/bluetooth_api.cc b/chrome/browser/extensions/api/bluetooth/bluetooth_api.cc
index 1d71950..9532f61 100644
--- a/chrome/browser/extensions/api/bluetooth/bluetooth_api.cc
+++ b/chrome/browser/extensions/api/bluetooth/bluetooth_api.cc
@@ -65,6 +65,7 @@ const char kStopDiscoveryFailed[] = "Failed to stop discovery";
 }  // namespace
 
 namespace AddProfile = extensions::api::bluetooth::AddProfile;
+namespace bluetooth = extensions::api::bluetooth;
 namespace Connect = extensions::api::bluetooth::Connect;
 namespace Disconnect = extensions::api::bluetooth::Disconnect;
 namespace GetDevices = extensions::api::bluetooth::GetDevices;
@@ -85,7 +86,7 @@ BluetoothAPI* BluetoothAPI::Get(Profile* profile) {
 
 BluetoothAPI::BluetoothAPI(Profile* profile) : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, extensions::event_names::kBluetoothOnAdapterStateChanged);
+      this, bluetooth::OnAdapterStateChanged::kEventName);
 }
 
 BluetoothAPI::~BluetoothAPI() {
diff --git a/chrome/browser/extensions/api/bluetooth/bluetooth_event_router.cc b/chrome/browser/extensions/api/bluetooth/bluetooth_event_router.cc
index 5147a7b..5162892 100644
--- a/chrome/browser/extensions/api/bluetooth/bluetooth_event_router.cc
+++ b/chrome/browser/extensions/api/bluetooth/bluetooth_event_router.cc
@@ -26,6 +26,8 @@
 
 namespace extensions {
 
+namespace bluetooth = api::bluetooth;
+
 ExtensionBluetoothEventRouter::ExtensionBluetoothEventRouter(Profile* profile)
     : send_discovery_events_(false),
       responsible_for_discovery_(false),
@@ -161,7 +163,7 @@ void ExtensionBluetoothEventRouter::SetSendDiscoveryEvents(bool should_send) {
 }
 
 void ExtensionBluetoothEventRouter::DispatchDeviceEvent(
-    const char* event_name, const extensions::api::bluetooth::Device& device) {
+    const char* event_name, const bluetooth::Device& device) {
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(device.ToValue().release());
   scoped_ptr<Event> event(new Event(event_name, args.Pass()));
@@ -185,7 +187,7 @@ void ExtensionBluetoothEventRouter::DispatchConnectionEvent(
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(result_socket.ToValue().release());
   scoped_ptr<Event> event(new Event(
-      extensions::event_names::kBluetoothOnConnection, args.Pass()));
+      bluetooth::OnConnection::kEventName, args.Pass()));
   ExtensionSystem::Get(profile_)->event_router()->DispatchEventToExtension(
       extension_id, event.Pass());
 }
@@ -232,9 +234,9 @@ void ExtensionBluetoothEventRouter::DeviceAdded(
     return;
   }
 
-  extensions::api::bluetooth::Device* extension_device =
-      new extensions::api::bluetooth::Device();
-  extensions::api::bluetooth::BluetoothDeviceToApiDevice(
+  bluetooth::Device* extension_device =
+      new bluetooth::Device();
+  bluetooth::BluetoothDeviceToApiDevice(
       *device, extension_device);
   discovered_devices_.push_back(extension_device);
 
@@ -274,7 +276,7 @@ void ExtensionBluetoothEventRouter::DispatchAdapterStateEvent() {
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(state.ToValue().release());
   scoped_ptr<Event> event(new Event(
-      extensions::event_names::kBluetoothOnAdapterStateChanged,
+      bluetooth::OnAdapterStateChanged::kEventName,
       args.Pass()));
   ExtensionSystem::Get(profile_)->event_router()->BroadcastEvent(event.Pass());
 }
diff --git a/chrome/browser/extensions/api/bluetooth/bluetooth_event_router_unittest.cc b/chrome/browser/extensions/api/bluetooth/bluetooth_event_router_unittest.cc
index 60b830a..39d3908 100644
--- a/chrome/browser/extensions/api/bluetooth/bluetooth_event_router_unittest.cc
+++ b/chrome/browser/extensions/api/bluetooth/bluetooth_event_router_unittest.cc
@@ -13,6 +13,7 @@
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system_factory.h"
 #include "chrome/browser/extensions/test_extension_system.h"
+#include "chrome/common/extensions/api/bluetooth.h"
 #include "chrome/test/base/testing_profile.h"
 #include "content/public/test/test_browser_thread.h"
 #include "device/bluetooth/test/mock_bluetooth_adapter.h"
@@ -79,6 +80,8 @@ BrowserContextKeyedService* BuildFakeExtensionSystem(
 
 namespace extensions {
 
+namespace bluetooth = api::bluetooth;
+
 class ExtensionBluetoothEventRouterTest : public testing::Test {
  public:
   ExtensionBluetoothEventRouterTest()
@@ -166,7 +169,7 @@ TEST_F(ExtensionBluetoothEventRouterTest, DispatchConnectionEvent) {
       static_cast<FakeEventRouter*>(fake_extension_system->event_router());
 
   EXPECT_STREQ(test_extension_id, fake_event_router->extension_id().c_str());
-  EXPECT_STREQ(event_names::kBluetoothOnConnection,
+  EXPECT_STREQ(bluetooth::OnConnection::kEventName,
                fake_event_router->event()->event_name.c_str());
 
   base::ListValue* event_args = fake_event_router->event()->event_args.get();
diff --git a/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api.cc b/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api.cc
index 9d25e6c..62ca111 100644
--- a/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api.cc
+++ b/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api.cc
@@ -42,6 +42,7 @@
 namespace extensions {
 
 namespace bookmark_keys = bookmark_api_constants;
+namespace bookmark_manager_private = api::bookmark_manager_private;
 namespace CanPaste = api::bookmark_manager_private::CanPaste;
 namespace Copy = api::bookmark_manager_private::Copy;
 namespace Cut = api::bookmark_manager_private::Cut;
@@ -198,7 +199,7 @@ void BookmarkManagerPrivateEventRouter::DispatchDragEvent(
 
 void BookmarkManagerPrivateEventRouter::OnDragEnter(
     const BookmarkNodeData& data) {
-  DispatchDragEvent(data, manager_keys::kOnBookmarkDragEnter);
+  DispatchDragEvent(data, bookmark_manager_private::OnDragEnter::kEventName);
 }
 
 void BookmarkManagerPrivateEventRouter::OnDragOver(
@@ -209,11 +210,11 @@ void BookmarkManagerPrivateEventRouter::OnDragOver(
 
 void BookmarkManagerPrivateEventRouter::OnDragLeave(
     const BookmarkNodeData& data) {
-  DispatchDragEvent(data, manager_keys::kOnBookmarkDragLeave);
+  DispatchDragEvent(data, bookmark_manager_private::OnDragLeave::kEventName);
 }
 
 void BookmarkManagerPrivateEventRouter::OnDrop(const BookmarkNodeData& data) {
-  DispatchDragEvent(data, manager_keys::kOnBookmarkDrop);
+  DispatchDragEvent(data, bookmark_manager_private::OnDrop::kEventName);
 
   // Make a copy that is owned by this instance.
   ClearBookmarkNodeData();
diff --git a/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api_constants.cc b/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api_constants.cc
index d7f7b4e..7818494 100644
--- a/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api_constants.cc
+++ b/chrome/browser/extensions/api/bookmark_manager_private/bookmark_manager_private_api_constants.cc
@@ -11,10 +11,5 @@ namespace bookmark_manager_api_constants {
 const char kSameProfileKey[] = "sameProfile";
 const char kElementsKey[] = "elements";
 
-// Events.
-const char kOnBookmarkDragEnter[] = "bookmarkManagerPrivate.onDragEnter";
-const char kOnBookmarkDragLeave[] = "bookmarkManagerPrivate.onDragLeave";
-const char kOnBookmarkDrop[] = "bookmarkManagerPrivate.onDrop";
-
 }  // namespace bookmark_manager_api_constants
 }  // namespace extensions
diff --git a/chrome/browser/extensions/api/bookmarks/bookmark_api_constants.cc b/chrome/browser/extensions/api/bookmarks/bookmark_api_constants.cc
index 32a03f2..b2bc4ad 100644
--- a/chrome/browser/extensions/api/bookmarks/bookmark_api_constants.cc
+++ b/chrome/browser/extensions/api/bookmarks/bookmark_api_constants.cc
@@ -30,13 +30,5 @@ const char kInvalidUrlError[] = "Invalid URL.";
 const char kModifySpecialError[] = "Can't modify the root bookmark folders.";
 const char kEditBookmarksDisabled[] = "Bookmark editing is disabled.";
 
-const char kOnBookmarkCreated[] = "bookmarks.onCreated";
-const char kOnBookmarkRemoved[] = "bookmarks.onRemoved";
-const char kOnBookmarkChanged[] = "bookmarks.onChanged";
-const char kOnBookmarkMoved[] = "bookmarks.onMoved";
-const char kOnBookmarkChildrenReordered[] = "bookmarks.onChildrenReordered";
-const char kOnBookmarkImportBegan[] = "bookmarks.onImportBegan";
-const char kOnBookmarkImportEnded[] = "bookmarks.onImportEnded";
-
 }  // namespace bookmark_api_constants
 }  // namespace extensions
diff --git a/chrome/browser/extensions/api/bookmarks/bookmarks_api.cc b/chrome/browser/extensions/api/bookmarks/bookmarks_api.cc
index a6a2d2a..f64299c 100644
--- a/chrome/browser/extensions/api/bookmarks/bookmarks_api.cc
+++ b/chrome/browser/extensions/api/bookmarks/bookmarks_api.cc
@@ -189,7 +189,7 @@ void BookmarkEventRouter::BookmarkNodeMoved(BookmarkModel* model,
   object_args->SetInteger(keys::kOldIndexKey, old_index);
   args->Append(object_args);
 
-  DispatchEvent(keys::kOnBookmarkMoved, args.Pass());
+  DispatchEvent(bookmarks::OnMoved::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::BookmarkNodeAdded(BookmarkModel* model,
@@ -202,7 +202,7 @@ void BookmarkEventRouter::BookmarkNodeAdded(BookmarkModel* model,
       bookmark_api_helpers::GetBookmarkTreeNode(node, false, false));
   args->Append(tree_node->ToValue().release());
 
-  DispatchEvent(keys::kOnBookmarkCreated, args.Pass());
+  DispatchEvent(bookmarks::OnCreated::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::BookmarkNodeRemoved(BookmarkModel* model,
@@ -217,7 +217,7 @@ void BookmarkEventRouter::BookmarkNodeRemoved(BookmarkModel* model,
   object_args->SetInteger(keys::kIndexKey, index);
   args->Append(object_args);
 
-  DispatchEvent(keys::kOnBookmarkRemoved, args.Pass());
+  DispatchEvent(bookmarks::OnRemoved::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::BookmarkAllNodesRemoved(BookmarkModel* model) {
@@ -243,7 +243,7 @@ void BookmarkEventRouter::BookmarkNodeChanged(BookmarkModel* model,
     object_args->SetString(keys::kUrlKey, node->url().spec());
   args->Append(object_args);
 
-  DispatchEvent(keys::kOnBookmarkChanged, args.Pass());
+  DispatchEvent(bookmarks::OnChanged::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::BookmarkNodeFaviconChanged(BookmarkModel* model,
@@ -268,35 +268,35 @@ void BookmarkEventRouter::BookmarkNodeChildrenReordered(
   reorder_info->Set(keys::kChildIdsKey, children);
   args->Append(reorder_info);
 
-  DispatchEvent(keys::kOnBookmarkChildrenReordered, args.Pass());
+  DispatchEvent(bookmarks::OnChildrenReordered::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::ExtensiveBookmarkChangesBeginning(
     BookmarkModel* model) {
   scoped_ptr<base::ListValue> args(new base::ListValue());
-  DispatchEvent(keys::kOnBookmarkImportBegan, args.Pass());
+  DispatchEvent(bookmarks::OnImportBegan::kEventName, args.Pass());
 }
 
 void BookmarkEventRouter::ExtensiveBookmarkChangesEnded(BookmarkModel* model) {
   scoped_ptr<base::ListValue> args(new base::ListValue());
-  DispatchEvent(keys::kOnBookmarkImportEnded, args.Pass());
+  DispatchEvent(bookmarks::OnImportEnded::kEventName, args.Pass());
 }
 
 BookmarksAPI::BookmarksAPI(Profile* profile) : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkCreated);
+      this, bookmarks::OnCreated::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkRemoved);
+      this, bookmarks::OnRemoved::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkChanged);
+      this, bookmarks::OnChanged::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkMoved);
+      this, bookmarks::OnMoved::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkChildrenReordered);
+      this, bookmarks::OnChildrenReordered::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkImportBegan);
+      this, bookmarks::OnImportBegan::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBookmarkImportEnded);
+      this, bookmarks::OnImportEnded::kEventName);
 }
 
 BookmarksAPI::~BookmarksAPI() {
diff --git a/chrome/browser/extensions/api/cookies/cookies_api.cc b/chrome/browser/extensions/api/cookies/cookies_api.cc
index afeaf8e..079be55 100644
--- a/chrome/browser/extensions/api/cookies/cookies_api.cc
+++ b/chrome/browser/extensions/api/cookies/cookies_api.cc
@@ -46,6 +46,7 @@ namespace Remove = extensions::api::cookies::Remove;
 namespace Set = extensions::api::cookies::Set;
 
 namespace extensions {
+namespace cookies = api::cookies;
 namespace keys = cookies_api_constants;
 
 CookiesEventRouter::CookiesEventRouter(Profile* profile)
@@ -123,7 +124,10 @@ void CookiesEventRouter::CookieChanged(
 
   GURL cookie_domain =
       cookies_helpers::GetURLFromCanonicalCookie(*details->cookie);
-  DispatchEvent(profile, keys::kOnChanged, args.Pass(), cookie_domain);
+  DispatchEvent(profile,
+                cookies::OnChanged::kEventName,
+                args.Pass(),
+                cookie_domain);
 }
 
 void CookiesEventRouter::DispatchEvent(
@@ -557,7 +561,7 @@ void CookiesGetAllCookieStoresFunction::Run() {
 CookiesAPI::CookiesAPI(Profile* profile)
     : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnChanged);
+      this, cookies::OnChanged::kEventName);
 }
 
 CookiesAPI::~CookiesAPI() {
diff --git a/chrome/browser/extensions/api/cookies/cookies_api_constants.cc b/chrome/browser/extensions/api/cookies/cookies_api_constants.cc
index ebbde77..58876b8 100644
--- a/chrome/browser/extensions/api/cookies/cookies_api_constants.cc
+++ b/chrome/browser/extensions/api/cookies/cookies_api_constants.cc
@@ -22,9 +22,6 @@ extern const char kExpiredOverwriteChangeCause[] = "expired_overwrite";
 extern const char kExplicitChangeCause[] = "explicit";
 extern const char kOverwriteChangeCause[] = "overwrite";
 
-// Events
-const char kOnChanged[] = "cookies.onChanged";
-
 // Errors
 const char kCookieSetFailedError[] =
     "Failed to parse or set cookie named \"*\".";
diff --git a/chrome/browser/extensions/api/debugger/debugger_api.cc b/chrome/browser/extensions/api/debugger/debugger_api.cc
index fd06dda..b2ca4c1 100644
--- a/chrome/browser/extensions/api/debugger/debugger_api.cc
+++ b/chrome/browser/extensions/api/debugger/debugger_api.cc
@@ -398,7 +398,7 @@ void ExtensionDevToolsClientHost::SendDetachedEvent() {
   scoped_ptr<base::ListValue> args(OnDetach::Create(debuggee_,
                                                     detach_reason_));
   scoped_ptr<extensions::Event> event(new extensions::Event(
-      keys::kOnDetach, args.Pass()));
+      OnDetach::kEventName, args.Pass()));
   event->restrict_to_profile = profile_;
   extensions::ExtensionSystem::Get(profile_)->event_router()->
       DispatchEventToExtension(extension_id_, event.Pass());
@@ -448,7 +448,7 @@ void ExtensionDevToolsClientHost::DispatchOnInspectorFrontend(
 
     scoped_ptr<ListValue> args(OnEvent::Create(debuggee_, method_name, params));
     scoped_ptr<extensions::Event> event(new extensions::Event(
-        keys::kOnEvent, args.Pass()));
+        OnEvent::kEventName, args.Pass()));
     event->restrict_to_profile = profile_;
     extensions::ExtensionSystem::Get(profile_)->event_router()->
         DispatchEventToExtension(extension_id_, event.Pass());
diff --git a/chrome/browser/extensions/api/debugger/debugger_api_constants.cc b/chrome/browser/extensions/api/debugger/debugger_api_constants.cc
index a9f5c6e..70da45b 100644
--- a/chrome/browser/extensions/api/debugger/debugger_api_constants.cc
+++ b/chrome/browser/extensions/api/debugger/debugger_api_constants.cc
@@ -6,9 +6,6 @@
 
 namespace debugger_api_constants {
 
-const char kOnEvent[] = "debugger.onEvent";
-const char kOnDetach[] = "debugger.onDetach";
-
 const char kAlreadyAttachedError[] =
     "Another debugger is already attached to the * with id: *.";
 const char kAttachToWebUIError[] =
diff --git a/chrome/browser/extensions/api/developer_private/developer_private_api.cc b/chrome/browser/extensions/api/developer_private/developer_private_api.cc
index 6c144fb..b5fa594 100644
--- a/chrome/browser/extensions/api/developer_private/developer_private_api.cc
+++ b/chrome/browser/extensions/api/developer_private/developer_private_api.cc
@@ -22,7 +22,6 @@
 #include "chrome/browser/extensions/api/developer_private/developer_private_api_factory.h"
 #include "chrome/browser/extensions/api/developer_private/entry_picker.h"
 #include "chrome/browser/extensions/api/extension_action/extension_action_api.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/extension_disabled_ui.h"
 #include "chrome/browser/extensions/extension_error_reporter.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -72,7 +71,7 @@ using content::RenderViewHost;
 
 namespace extensions {
 
-namespace events = event_names;
+namespace developer_private = api::developer_private;
 
 namespace {
 
@@ -212,7 +211,7 @@ void DeveloperPrivateEventRouter::Observe(
   scoped_ptr<ListValue> args(new ListValue());
   args->Append(event_data.ToValue().release());
 
-  event_name = events::kDeveloperPrivateOnItemStateChanged;
+  event_name = developer_private::OnItemStateChanged::kEventName;
   scoped_ptr<Event> event(new Event(event_name, args.Pass()));
   ExtensionSystem::Get(profile)->event_router()->BroadcastEvent(event.Pass());
 }
@@ -223,7 +222,7 @@ void DeveloperPrivateAPI::SetLastUnpackedDirectory(const base::FilePath& path) {
 
 void DeveloperPrivateAPI::RegisterNotifications() {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, events::kDeveloperPrivateOnItemStateChanged);
+      this, developer_private::OnItemStateChanged::kEventName);
 }
 
 DeveloperPrivateAPI::~DeveloperPrivateAPI() {}
@@ -240,7 +239,7 @@ void DeveloperPrivateAPI::OnListenerAdded(
 void DeveloperPrivateAPI::OnListenerRemoved(
     const EventListenerInfo& details) {
   if (!ExtensionSystem::Get(profile_)->event_router()->HasEventListener(
-          event_names::kDeveloperPrivateOnItemStateChanged))
+          developer_private::OnItemStateChanged::kEventName))
     developer_private_event_router_.reset(NULL);
 }
 
diff --git a/chrome/browser/extensions/api/dial/dial_api.cc b/chrome/browser/extensions/api/dial/dial_api.cc
index 02f6d82..062fc6f 100644
--- a/chrome/browser/extensions/api/dial/dial_api.cc
+++ b/chrome/browser/extensions/api/dial/dial_api.cc
@@ -8,7 +8,6 @@
 
 #include "base/time/time.h"
 #include "chrome/browser/extensions/api/dial/dial_api_factory.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
@@ -35,11 +34,13 @@ const size_t kDialMaxDevices = 256;
 
 namespace extensions {
 
+namespace dial = api::dial;
+
 DialAPI::DialAPI(Profile* profile)
     : RefcountedBrowserContextKeyedService(BrowserThread::IO),
       profile_(profile) {
   ExtensionSystem::Get(profile)->event_router()->RegisterObserver(
-      this, extensions::event_names::kOnDialDeviceList);
+      this, dial::OnDeviceList::kEventName);
 }
 
 DialAPI::~DialAPI() {}
@@ -106,7 +107,7 @@ void DialAPI::SendEventOnUIThread(const DialRegistry::DeviceList& devices) {
   }
   scoped_ptr<base::ListValue> results = api::dial::OnDeviceList::Create(args);
   scoped_ptr<Event> event(
-      new Event(event_names::kOnDialDeviceList, results.Pass()));
+      new Event(dial::OnDeviceList::kEventName, results.Pass()));
   extensions::ExtensionSystem::Get(profile_)->event_router()->
       BroadcastEvent(event.Pass());
 }
@@ -137,7 +138,7 @@ void DialAPI::SendErrorOnUIThread(const DialRegistry::DialErrorCode code) {
   }
 
   scoped_ptr<base::ListValue> results = api::dial::OnError::Create(dial_error);
-  scoped_ptr<Event> event(new Event(event_names::kOnDialError, results.Pass()));
+  scoped_ptr<Event> event(new Event(dial::OnError::kEventName, results.Pass()));
   extensions::ExtensionSystem::Get(profile_)->event_router()->
       BroadcastEvent(event.Pass());
 }
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.cc b/chrome/browser/extensions/api/downloads/downloads_api.cc
index 7cc8a48..aeeac02 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api.cc
@@ -38,7 +38,6 @@
 #include "chrome/browser/download/download_shelf.h"
 #include "chrome/browser/download/download_stats.h"
 #include "chrome/browser/download/download_util.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_function_dispatcher.h"
 #include "chrome/browser/extensions/extension_info_map.h"
@@ -79,8 +78,6 @@
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/webui/web_ui_util.h"
 
-namespace events = extensions::event_names;
-
 using content::BrowserContext;
 using content::BrowserThread;
 using content::DownloadItem;
@@ -121,6 +118,8 @@ namespace errors = download_extension_errors;
 
 namespace {
 
+namespace downloads = extensions::api::downloads;
+
 // Default icon size for getFileIcon() in pixels.
 const int  kDefaultIconSize = 32;
 
@@ -476,7 +475,7 @@ void CompileDownloadQueryOrderBy(
 }
 
 void RunDownloadQuery(
-    const extensions::api::downloads::DownloadQuery& query_in,
+    const downloads::DownloadQuery& query_in,
     DownloadManager* manager,
     DownloadManager* incognito_manager,
     std::string* error,
@@ -503,7 +502,7 @@ void RunDownloadQuery(
   }
 
   std::string state_string =
-      extensions::api::downloads::ToString(query_in.state);
+      downloads::ToString(query_in.state);
   if (!state_string.empty()) {
     DownloadItem::DownloadState state = StateEnumFromString(state_string);
     if (state == DownloadItem::MAX_DOWNLOAD_STATE) {
@@ -513,7 +512,7 @@ void RunDownloadQuery(
     query_out.AddFilter(state);
   }
   std::string danger_string =
-      extensions::api::downloads::ToString(query_in.danger);
+      downloads::ToString(query_in.danger);
   if (!danger_string.empty()) {
     content::DownloadDangerType danger_type = DangerEnumFromString(
         danger_string);
@@ -559,14 +558,14 @@ void RunDownloadQuery(
 }
 
 DownloadPathReservationTracker::FilenameConflictAction ConvertConflictAction(
-    extensions::api::downloads::FilenameConflictAction action) {
+    downloads::FilenameConflictAction action) {
   switch (action) {
-    case extensions::api::downloads::FILENAME_CONFLICT_ACTION_NONE:
-    case extensions::api::downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY:
+    case downloads::FILENAME_CONFLICT_ACTION_NONE:
+    case downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY:
       return DownloadPathReservationTracker::UNIQUIFY;
-    case extensions::api::downloads::FILENAME_CONFLICT_ACTION_OVERWRITE:
+    case downloads::FILENAME_CONFLICT_ACTION_OVERWRITE:
       return DownloadPathReservationTracker::OVERWRITE;
-    case extensions::api::downloads::FILENAME_CONFLICT_ACTION_PROMPT:
+    case downloads::FILENAME_CONFLICT_ACTION_PROMPT:
       return DownloadPathReservationTracker::PROMPT;
   }
   NOTREACHED();
@@ -592,9 +591,9 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
         changed_fired_(0),
         json_(json_item.Pass()),
         creator_conflict_action_(
-            extensions::api::downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY),
+            downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY),
         determined_conflict_action_(
-            extensions::api::downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY) {
+            downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY) {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     download_item->SetUserData(kKey, this);
   }
@@ -630,7 +629,7 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     determined_filename_.clear();
     determined_conflict_action_ =
-      extensions::api::downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY;
+      downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY;
     determiner_ = DeterminerInfo();
     filename_no_change_ = base::Closure();
     filename_change_ = ExtensionDownloadsEventRouter::FilenameChangedCallback();
@@ -677,7 +676,7 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
 
   void CreatorSuggestedFilename(
       const base::FilePath& filename,
-      extensions::api::downloads::FilenameConflictAction conflict_action) {
+      downloads::FilenameConflictAction conflict_action) {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     creator_suggested_filename_ = filename;
     creator_conflict_action_ = conflict_action;
@@ -687,7 +686,7 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
     return creator_suggested_filename_;
   }
 
-  extensions::api::downloads::FilenameConflictAction
+  downloads::FilenameConflictAction
   creator_conflict_action() const {
     return creator_conflict_action_;
   }
@@ -696,7 +695,7 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     creator_suggested_filename_.clear();
     creator_conflict_action_ =
-      extensions::api::downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY;
+      downloads::FILENAME_CONFLICT_ACTION_UNIQUIFY;
   }
 
   // Returns false if this |extension_id| was not expected or if this
@@ -706,7 +705,7 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
       Profile* profile,
       const std::string& extension_id,
       const base::FilePath& filename,
-      extensions::api::downloads::FilenameConflictAction conflict_action) {
+      downloads::FilenameConflictAction conflict_action) {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     bool found_info = false;
     for (size_t index = 0; index < determiners_.size(); ++index) {
@@ -803,10 +802,10 @@ class ExtensionDownloadsEventRouterData : public base::SupportsUserData::Data {
   DeterminerInfoVector determiners_;
 
   base::FilePath creator_suggested_filename_;
-  extensions::api::downloads::FilenameConflictAction
+  downloads::FilenameConflictAction
     creator_conflict_action_;
   base::FilePath determined_filename_;
-  extensions::api::downloads::FilenameConflictAction
+  downloads::FilenameConflictAction
     determined_conflict_action_;
   DeterminerInfo determiner_;
 
@@ -957,10 +956,10 @@ DownloadsDownloadFunction::DownloadsDownloadFunction() {}
 DownloadsDownloadFunction::~DownloadsDownloadFunction() {}
 
 bool DownloadsDownloadFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Download::Params> params(
-      extensions::api::downloads::Download::Params::Create(*args_));
+  scoped_ptr<downloads::Download::Params> params(
+      downloads::Download::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
-  const extensions::api::downloads::DownloadOptions& options = params->options;
+  const downloads::DownloadOptions& options = params->options;
   GURL download_url(options.url);
   if (Fault(!download_url.is_valid(), errors::kInvalidURL, &error_))
     return false;
@@ -1000,7 +999,7 @@ bool DownloadsDownloadFunction::RunImpl() {
     download_params->set_prompt(*options.save_as.get());
 
   if (options.headers.get()) {
-    typedef extensions::api::downloads::HeaderNameValuePair HeaderNameValuePair;
+    typedef downloads::HeaderNameValuePair HeaderNameValuePair;
     for (std::vector<linked_ptr<HeaderNameValuePair> >::const_iterator iter =
          options.headers->begin();
          iter != options.headers->end();
@@ -1015,7 +1014,7 @@ bool DownloadsDownloadFunction::RunImpl() {
   }
 
   std::string method_string =
-      extensions::api::downloads::ToString(options.method);
+      downloads::ToString(options.method);
   if (!method_string.empty())
     download_params->set_method(method_string);
   if (options.body.get())
@@ -1036,7 +1035,7 @@ bool DownloadsDownloadFunction::RunImpl() {
 
 void DownloadsDownloadFunction::OnStarted(
     const base::FilePath& creator_suggested_filename,
-    extensions::api::downloads::FilenameConflictAction creator_conflict_action,
+    downloads::FilenameConflictAction creator_conflict_action,
     DownloadItem* item,
     net::Error error) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ -1070,8 +1069,8 @@ DownloadsSearchFunction::DownloadsSearchFunction() {}
 DownloadsSearchFunction::~DownloadsSearchFunction() {}
 
 bool DownloadsSearchFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Search::Params> params(
-      extensions::api::downloads::Search::Params::Create(*args_));
+  scoped_ptr<downloads::Search::Params> params(
+      downloads::Search::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadManager* manager = NULL;
   DownloadManager* incognito_manager = NULL;
@@ -1109,8 +1108,8 @@ DownloadsPauseFunction::DownloadsPauseFunction() {}
 DownloadsPauseFunction::~DownloadsPauseFunction() {}
 
 bool DownloadsPauseFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Pause::Params> params(
-      extensions::api::downloads::Pause::Params::Create(*args_));
+  scoped_ptr<downloads::Pause::Params> params(
+      downloads::Pause::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1130,8 +1129,8 @@ DownloadsResumeFunction::DownloadsResumeFunction() {}
 DownloadsResumeFunction::~DownloadsResumeFunction() {}
 
 bool DownloadsResumeFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Resume::Params> params(
-      extensions::api::downloads::Resume::Params::Create(*args_));
+  scoped_ptr<downloads::Resume::Params> params(
+      downloads::Resume::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1151,8 +1150,8 @@ DownloadsCancelFunction::DownloadsCancelFunction() {}
 DownloadsCancelFunction::~DownloadsCancelFunction() {}
 
 bool DownloadsCancelFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Resume::Params> params(
-      extensions::api::downloads::Resume::Params::Create(*args_));
+  scoped_ptr<downloads::Resume::Params> params(
+      downloads::Resume::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1170,8 +1169,8 @@ DownloadsEraseFunction::DownloadsEraseFunction() {}
 DownloadsEraseFunction::~DownloadsEraseFunction() {}
 
 bool DownloadsEraseFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Erase::Params> params(
-      extensions::api::downloads::Erase::Params::Create(*args_));
+  scoped_ptr<downloads::Erase::Params> params(
+      downloads::Erase::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadManager* manager = NULL;
   DownloadManager* incognito_manager = NULL;
@@ -1206,8 +1205,8 @@ DownloadsRemoveFileFunction::~DownloadsRemoveFileFunction() {
 }
 
 bool DownloadsRemoveFileFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::RemoveFile::Params> params(
-      extensions::api::downloads::RemoveFile::Params::Create(*args_));
+  scoped_ptr<downloads::RemoveFile::Params> params(
+      downloads::RemoveFile::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1247,8 +1246,8 @@ DownloadsAcceptDangerFunction::DownloadsAcceptDangerFunction() {}
 DownloadsAcceptDangerFunction::~DownloadsAcceptDangerFunction() {}
 
 bool DownloadsAcceptDangerFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::AcceptDanger::Params> params(
-      extensions::api::downloads::AcceptDanger::Params::Create(*args_));
+  scoped_ptr<downloads::AcceptDanger::Params> params(
+      downloads::AcceptDanger::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1300,8 +1299,8 @@ DownloadsShowFunction::DownloadsShowFunction() {}
 DownloadsShowFunction::~DownloadsShowFunction() {}
 
 bool DownloadsShowFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Show::Params> params(
-      extensions::api::downloads::Show::Params::Create(*args_));
+  scoped_ptr<downloads::Show::Params> params(
+      downloads::Show::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1331,8 +1330,8 @@ DownloadsOpenFunction::DownloadsOpenFunction() {}
 DownloadsOpenFunction::~DownloadsOpenFunction() {}
 
 bool DownloadsOpenFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Open::Params> params(
-      extensions::api::downloads::Open::Params::Create(*args_));
+  scoped_ptr<downloads::Open::Params> params(
+      downloads::Open::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1353,8 +1352,8 @@ DownloadsDragFunction::DownloadsDragFunction() {}
 DownloadsDragFunction::~DownloadsDragFunction() {}
 
 bool DownloadsDragFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::Drag::Params> params(
-      extensions::api::downloads::Drag::Params::Create(*args_));
+  scoped_ptr<downloads::Drag::Params> params(
+      downloads::Drag::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   DownloadItem* download_item = GetDownload(
       profile(), include_incognito(), params->download_id);
@@ -1381,8 +1380,8 @@ DownloadsSetShelfEnabledFunction::DownloadsSetShelfEnabledFunction() {}
 DownloadsSetShelfEnabledFunction::~DownloadsSetShelfEnabledFunction() {}
 
 bool DownloadsSetShelfEnabledFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::SetShelfEnabled::Params> params(
-      extensions::api::downloads::SetShelfEnabled::Params::Create(*args_));
+  scoped_ptr<downloads::SetShelfEnabled::Params> params(
+      downloads::SetShelfEnabled::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   if (!GetExtension()->HasAPIPermission(
         extensions::APIPermission::kDownloadsShelf)) {
@@ -1447,10 +1446,10 @@ void DownloadsGetFileIconFunction::SetIconExtractorForTesting(
 }
 
 bool DownloadsGetFileIconFunction::RunImpl() {
-  scoped_ptr<extensions::api::downloads::GetFileIcon::Params> params(
-      extensions::api::downloads::GetFileIcon::Params::Create(*args_));
+  scoped_ptr<downloads::GetFileIcon::Params> params(
+      downloads::GetFileIcon::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
-  const extensions::api::downloads::GetFileIconOptions* options =
+  const downloads::GetFileIconOptions* options =
       params->options.get();
   int icon_size = kDefaultIconSize;
   if (options && options->size.get())
@@ -1496,7 +1495,8 @@ ExtensionDownloadsEventRouter::ExtensionDownloadsEventRouter(
   extensions::EventRouter* router = extensions::ExtensionSystem::Get(profile_)->
       event_router();
   if (router)
-    router->RegisterObserver(this, events::kOnDownloadDeterminingFilename);
+    router->RegisterObserver(this,
+                             downloads::OnDeterminingFilename::kEventName);
 }
 
 ExtensionDownloadsEventRouter::~ExtensionDownloadsEventRouter() {
@@ -1566,7 +1566,7 @@ void ExtensionDownloadsEventRouter::OnDeterminingFilename(
   base::DictionaryValue* json = DownloadItemToJSON(
       item, profile_).release();
   json->SetString(kFilenameKey, suggested_path.LossyDisplayName());
-  DispatchEvent(events::kOnDownloadDeterminingFilename,
+  DispatchEvent(downloads::OnDeterminingFilename::kEventName,
                 false,
                 base::Bind(&OnDeterminingFilenameWillDispatchCallback,
                            &any_determiners,
@@ -1587,14 +1587,14 @@ void ExtensionDownloadsEventRouter::OnDeterminingFilename(
 
 void ExtensionDownloadsEventRouter::DetermineFilenameInternal(
     const base::FilePath& filename,
-    extensions::api::downloads::FilenameConflictAction conflict_action,
+    downloads::FilenameConflictAction conflict_action,
     const std::string& suggesting_extension_id,
     const base::Time& suggesting_install_time,
     const std::string& incumbent_extension_id,
     const base::Time& incumbent_install_time,
     std::string* winner_extension_id,
     base::FilePath* determined_filename,
-    extensions::api::downloads::FilenameConflictAction*
+    downloads::FilenameConflictAction*
       determined_conflict_action,
     extensions::ExtensionWarningSet* warnings) {
   DCHECK(!filename.empty());
@@ -1635,7 +1635,7 @@ bool ExtensionDownloadsEventRouter::DetermineFilename(
     const std::string& ext_id,
     int download_id,
     const base::FilePath& const_filename,
-    extensions::api::downloads::FilenameConflictAction conflict_action,
+    downloads::FilenameConflictAction conflict_action,
     std::string* error) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DownloadItem* item = GetDownload(profile, include_incognito, download_id);
@@ -1678,12 +1678,12 @@ void ExtensionDownloadsEventRouter::OnListenerRemoved(
   if (!manager)
     return;
   bool determiner_removed = (
-      details.event_name == events::kOnDownloadDeterminingFilename);
+      details.event_name == downloads::OnDeterminingFilename::kEventName);
   extensions::EventRouter* router = extensions::ExtensionSystem::Get(profile_)->
       event_router();
   bool any_listeners =
-    router->HasEventListener(events::kOnDownloadChanged) ||
-    router->HasEventListener(events::kOnDownloadDeterminingFilename);
+    router->HasEventListener(downloads::OnChanged::kEventName) ||
+    router->HasEventListener(downloads::OnDeterminingFilename::kEventName);
   if (!determiner_removed && any_listeners)
     return;
   DownloadManager::DownloadVector items;
@@ -1724,20 +1724,22 @@ void ExtensionDownloadsEventRouter::OnDownloadCreated(
   // Avoid allocating a bunch of memory in DownloadItemToJSON if it isn't going
   // to be used.
   if (!router ||
-      (!router->HasEventListener(events::kOnDownloadCreated) &&
-       !router->HasEventListener(events::kOnDownloadChanged) &&
-       !router->HasEventListener(events::kOnDownloadDeterminingFilename))) {
+      (!router->HasEventListener(downloads::OnCreated::kEventName) &&
+       !router->HasEventListener(downloads::OnChanged::kEventName) &&
+       !router->HasEventListener(
+            downloads::OnDeterminingFilename::kEventName))) {
     return;
   }
   scoped_ptr<base::DictionaryValue> json_item(
       DownloadItemToJSON(download_item, profile_));
-  DispatchEvent(events::kOnDownloadCreated,
+  DispatchEvent(downloads::OnCreated::kEventName,
                 true,
                 extensions::Event::WillDispatchCallback(),
                 json_item->DeepCopy());
   if (!ExtensionDownloadsEventRouterData::Get(download_item) &&
-      (router->HasEventListener(events::kOnDownloadChanged) ||
-       router->HasEventListener(events::kOnDownloadDeterminingFilename))) {
+      (router->HasEventListener(downloads::OnChanged::kEventName) ||
+       router->HasEventListener(
+           downloads::OnDeterminingFilename::kEventName))) {
     new ExtensionDownloadsEventRouterData(download_item, json_item.Pass());
   }
 }
@@ -1750,7 +1752,7 @@ void ExtensionDownloadsEventRouter::OnDownloadUpdated(
   ExtensionDownloadsEventRouterData* data =
     ExtensionDownloadsEventRouterData::Get(download_item);
   if (download_item->IsTemporary() ||
-      !router->HasEventListener(events::kOnDownloadChanged)) {
+      !router->HasEventListener(downloads::OnChanged::kEventName)) {
     return;
   }
   if (!data) {
@@ -1803,7 +1805,7 @@ void ExtensionDownloadsEventRouter::OnDownloadUpdated(
   // changed. Replace the stored json with the new json.
   data->OnItemUpdated();
   if (changed) {
-    DispatchEvent(events::kOnDownloadChanged,
+    DispatchEvent(downloads::OnChanged::kEventName,
                   true,
                   extensions::Event::WillDispatchCallback(),
                   delta.release());
@@ -1817,7 +1819,7 @@ void ExtensionDownloadsEventRouter::OnDownloadRemoved(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (download_item->IsTemporary())
     return;
-  DispatchEvent(events::kOnDownloadErased,
+  DispatchEvent(downloads::OnErased::kEventName,
                 true,
                 extensions::Event::WillDispatchCallback(),
                 new base::FundamentalValue(
diff --git a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
index e5962af..98c5f48 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
@@ -18,7 +18,6 @@
 #include "chrome/browser/download/download_service_factory.h"
 #include "chrome/browser/download/download_test_file_activity_observer.h"
 #include "chrome/browser/extensions/api/downloads/downloads_api.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/extensions/extension_function_test_utils.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -58,8 +57,6 @@ using content::DownloadItem;
 using content::DownloadManager;
 using content::URLRequestSlowDownloadJob;
 
-namespace events = extensions::event_names;
-
 namespace errors = download_extension_errors;
 
 namespace api = extensions::api::downloads;
@@ -116,9 +113,9 @@ class DownloadsEventsListener : public content::NotificationObserver {
       if ((profile_ != other.profile_) ||
           (event_name_ != other.event_name_))
         return false;
-      if (((event_name_ == events::kOnDownloadDeterminingFilename) ||
-           (event_name_ == events::kOnDownloadCreated) ||
-           (event_name_ == events::kOnDownloadChanged)) &&
+      if (((event_name_ == api::OnDeterminingFilename::kEventName) ||
+           (event_name_ == api::OnCreated::kEventName) ||
+           (event_name_ == api::OnChanged::kEventName)) &&
           args_.get() &&
           other.args_.get()) {
         base::ListValue* left_list = NULL;
@@ -140,7 +137,7 @@ class DownloadsEventsListener : public content::NotificationObserver {
           }
         }
         return true;
-      } else if ((event_name_ == events::kOnDownloadErased) &&
+      } else if ((event_name_ == api::OnErased::kEventName) &&
                  args_.get() &&
                  other.args_.get()) {
         int my_id = -1, other_id = -1;
@@ -277,17 +274,17 @@ class DownloadExtensionTest : public ExtensionApiTest {
         content::PAGE_TRANSITION_LINK);
     extensions::ExtensionSystem::Get(current_browser()->profile())->
       event_router()->AddEventListener(
-          extensions::event_names::kOnDownloadCreated,
+          api::OnCreated::kEventName,
           tab->GetRenderProcessHost(),
           GetExtensionId());
     extensions::ExtensionSystem::Get(current_browser()->profile())->
       event_router()->AddEventListener(
-          extensions::event_names::kOnDownloadChanged,
+          api::OnChanged::kEventName,
           tab->GetRenderProcessHost(),
           GetExtensionId());
     extensions::ExtensionSystem::Get(current_browser()->profile())->
       event_router()->AddEventListener(
-          extensions::event_names::kOnDownloadErased,
+          api::OnErased::kEventName,
           tab->GetRenderProcessHost(),
           GetExtensionId());
   }
@@ -299,7 +296,7 @@ class DownloadExtensionTest : public ExtensionApiTest {
         content::PAGE_TRANSITION_LINK);
     extensions::ExtensionSystem::Get(current_browser()->profile())->
       event_router()->AddEventListener(
-          extensions::event_names::kOnDownloadDeterminingFilename,
+          api::OnDeterminingFilename::kEventName,
           tab->GetRenderProcessHost(),
           GetExtensionId());
     return tab->GetRenderProcessHost();
@@ -308,7 +305,7 @@ class DownloadExtensionTest : public ExtensionApiTest {
   void RemoveFilenameDeterminer(content::RenderProcessHost* host) {
     extensions::ExtensionSystem::Get(current_browser()->profile())->
       event_router()->RemoveEventListener(
-          extensions::event_names::kOnDownloadDeterminingFilename,
+          api::OnDeterminingFilename::kEventName,
           host,
           GetExtensionId());
   }
@@ -355,10 +352,10 @@ class DownloadExtensionTest : public ExtensionApiTest {
       DownloadItem* item,
       content::DownloadInterruptReason expected_error,
       const std::string& on_created_event) {
-    if (!WaitFor(events::kOnDownloadCreated, on_created_event))
+    if (!WaitFor(api::OnCreated::kEventName, on_created_event))
       return false;
     // Now, onCreated is always fired before interruption.
-    return WaitFor(events::kOnDownloadChanged,
+    return WaitFor(api::OnChanged::kEventName,
         base::StringPrintf("[{\"id\": %d,"
                            "  \"error\": {\"current\": \"%s\"},"
                            "  \"state\": {"
@@ -814,7 +811,7 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ASSERT_TRUE(download_item);
   EXPECT_FALSE(download_item->GetOpened());
   EXPECT_FALSE(download_item->GetOpenWhenComplete());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"application/octet-stream\","
@@ -1445,21 +1442,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"text/plain\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -1489,21 +1486,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": true,"
                          "  \"mime\": \"text/plain\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\":%d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\":%d,"
                          "  \"state\": {"
                          "    \"current\": \"complete\","
@@ -1600,21 +1597,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"text/plain\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("sub/dir/ect/ory.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -1697,21 +1694,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"text/plain\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -1738,21 +1735,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"text/plain\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("data.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -1790,21 +1787,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"mime\": \"text/html\","
                           "  \"paused\": false,"
                           "  \"url\": \"%s\"}]",
                           download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"filename\": {"
                           "    \"previous\": \"\","
                           "    \"current\": \"%s\"}}]",
                           result_id,
                           GetFilename("file.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -1874,21 +1871,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"application/octet-stream\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]",
                          download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("headers-succeed.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -1962,13 +1959,13 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"mime\": \"text/html\","
                           "  \"paused\": false,"
                           "  \"url\": \"%s\"}]", download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -2001,20 +1998,20 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"mime\": \"application/octet-stream\","
                          "  \"paused\": false,"
                          "  \"url\": \"%s\"}]", download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("post-succeed.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2128,7 +2125,7 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"mime\": \"application/octet-stream\","
@@ -2138,7 +2135,7 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
                           result_id,
                           download_url.c_str())));
   item->Cancel(true);
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"error\": {\"current\":\"USER_CANCELED\"},"
                           "  \"state\": {"
@@ -2178,21 +2175,21 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"mime\": \"text/plain\","
                           "  \"paused\": false,"
                           "  \"url\": \"%s\"}]",
                           download_url.c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"filename\": {"
                           "    \"previous\": \"\","
                           "    \"current\": \"%s\"}}]",
                           result_id,
                           GetFilename("on_record.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -2226,7 +2223,7 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
   // Wait for the onCreated and onDeterminingFilename events.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2236,7 +2233,7 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2256,14 +2253,14 @@ IN_PROC_BROWSER_TEST_F(DownloadExtensionTest,
   EXPECT_EQ("", error);
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2293,7 +2290,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2303,7 +2300,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2322,7 +2319,7 @@ IN_PROC_BROWSER_TEST_F(
       &error));
   EXPECT_EQ("", error);
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"danger\": {"
                          "    \"previous\":\"safe\","
@@ -2330,13 +2327,13 @@ IN_PROC_BROWSER_TEST_F(
                          result_id)));
 
   item->ValidateDangerousDownload();
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"danger\": {"
                          "    \"previous\":\"file\","
                          "    \"current\":\"accepted\"}}]",
                          result_id)));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -2368,7 +2365,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2378,7 +2375,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2396,14 +2393,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"filename\": {"
                           "    \"previous\": \"\","
                           "    \"current\": \"%s\"}}]",
                           result_id,
                           GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -2433,7 +2430,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2443,7 +2440,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2461,14 +2458,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"filename\": {"
       "    \"previous\": \"\","
       "    \"current\": \"%s\"}}]",
       result_id,
       GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"state\": {"
       "    \"previous\": \"in_progress\","
@@ -2498,7 +2495,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2508,7 +2505,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2527,14 +2524,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"filename\": {"
       "    \"previous\": \"\","
       "    \"current\": \"%s\"}}]",
       result_id,
       GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"state\": {"
       "    \"previous\": \"in_progress\","
@@ -2564,7 +2561,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2574,7 +2571,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2592,14 +2589,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"filename\": {"
       "    \"previous\": \"\","
       "    \"current\": \"%s\"}}]",
       result_id,
       GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged, base::StringPrintf(
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName, base::StringPrintf(
       "[{\"id\": %d,"
       "  \"state\": {"
       "    \"previous\": \"in_progress\","
@@ -2629,7 +2626,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2639,7 +2636,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2657,14 +2654,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2694,7 +2691,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2704,7 +2701,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2722,14 +2719,14 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2759,7 +2756,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2769,7 +2766,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2788,14 +2785,14 @@ IN_PROC_BROWSER_TEST_F(
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"filename\": {"
                           "    \"previous\": \"\","
                           "    \"current\": \"%s\"}}]",
                           result_id,
                           GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                           "  \"state\": {"
                           "    \"previous\": \"in_progress\","
@@ -2825,7 +2822,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -2835,7 +2832,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2854,14 +2851,14 @@ IN_PROC_BROWSER_TEST_F(
       &error));
   EXPECT_STREQ(errors::kInvalidFilename, error.c_str());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2890,7 +2887,7 @@ IN_PROC_BROWSER_TEST_F(
   ASSERT_TRUE(item);
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"id\": %d,"
@@ -2900,7 +2897,7 @@ IN_PROC_BROWSER_TEST_F(
                          result_id,
                          download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2919,14 +2916,14 @@ IN_PROC_BROWSER_TEST_F(
       &error));
   EXPECT_EQ("", error);
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("slow.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -2945,7 +2942,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller2(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"id\": %d,"
@@ -2955,7 +2952,7 @@ IN_PROC_BROWSER_TEST_F(
                          result_id,
                          download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -2977,14 +2974,14 @@ IN_PROC_BROWSER_TEST_F(
       &error));
   EXPECT_EQ("", error);
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("foo").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3016,7 +3013,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -3026,7 +3023,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\":\"slow.txt\"}]",
                          result_id)));
@@ -3036,7 +3033,7 @@ IN_PROC_BROWSER_TEST_F(
   // Remove a determiner while waiting for it.
   RemoveFilenameDeterminer(host);
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3072,7 +3069,7 @@ IN_PROC_BROWSER_TEST_F(
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
   // Wait for the onCreated and onDeterminingFilename events.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -3082,7 +3079,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"incognito\": false,"
                          "  \"filename\":\"slow.txt\"}]",
@@ -3103,14 +3100,14 @@ IN_PROC_BROWSER_TEST_F(
   EXPECT_EQ("", error);
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("42.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3130,7 +3127,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller2(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": true,"
                          "  \"id\": %d,"
@@ -3141,7 +3138,7 @@ IN_PROC_BROWSER_TEST_F(
                          download_url.c_str())));
   // On-Record renderers should not see events for off-record items.
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"incognito\": true,"
                          "  \"filename\":\"slow.txt\"}]",
@@ -3162,14 +3159,14 @@ IN_PROC_BROWSER_TEST_F(
   EXPECT_EQ("", error);
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("5.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3206,7 +3203,7 @@ IN_PROC_BROWSER_TEST_F(
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
   // Wait for the onCreated and onDeterminingFilename events.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                           "  \"incognito\": false,"
                           "  \"id\": %d,"
@@ -3216,7 +3213,7 @@ IN_PROC_BROWSER_TEST_F(
                           result_id,
                           download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"incognito\": false,"
                          "  \"filename\":\"slow.txt\"}]",
@@ -3237,14 +3234,14 @@ IN_PROC_BROWSER_TEST_F(
   EXPECT_EQ("", error);
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("42.txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3264,7 +3261,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller2(item);
   ASSERT_EQ(download_url, item->GetOriginalUrl().spec());
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": true,"
                          "  \"id\": %d,"
@@ -3274,7 +3271,7 @@ IN_PROC_BROWSER_TEST_F(
                          result_id,
                          download_url.c_str())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"incognito\": true,"
                          "  \"filename\":\"slow.txt\"}]",
@@ -3295,14 +3292,14 @@ IN_PROC_BROWSER_TEST_F(
   EXPECT_EQ("", error);
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
                          "    \"current\": \"%s\"}}]",
                          result_id,
                          GetFilename("42 (1).txt").c_str())));
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
@@ -3364,7 +3361,7 @@ IN_PROC_BROWSER_TEST_F(
   ScopedCancellingItem canceller(item);
 
   // Wait for the onCreated and onDeterminingFilename event.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadCreated,
+  ASSERT_TRUE(WaitFor(api::OnCreated::kEventName,
       base::StringPrintf("[{\"danger\": \"safe\","
                          "  \"incognito\": false,"
                          "  \"id\": %d,"
@@ -3372,7 +3369,7 @@ IN_PROC_BROWSER_TEST_F(
                          "  \"paused\": false}]",
                          item->GetId())));
   ASSERT_TRUE(WaitFor(
-      events::kOnDownloadDeterminingFilename,
+      api::OnDeterminingFilename::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"incognito\": false,"
                          "  \"filename\":\"download-unknown-size\"}]",
@@ -3399,7 +3396,7 @@ IN_PROC_BROWSER_TEST_F(
       api::FILENAME_CONFLICT_ACTION_UNIQUIFY,
       &error)) << error;
   EXPECT_EQ("", error);
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"filename\": {"
                          "    \"previous\": \"\","
@@ -3410,7 +3407,7 @@ IN_PROC_BROWSER_TEST_F(
   content::DownloadUpdatedObserver interrupted(item, base::Bind(
       ItemIsInterrupted));
   ASSERT_TRUE(interrupted.WaitForEvent());
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"error\":{\"current\":\"NETWORK_FAILED\"},"
                          "  \"state\":{"
@@ -3429,7 +3426,7 @@ IN_PROC_BROWSER_TEST_F(
   // does not need to be re-done. So, there will not be a second
   // onDeterminingFilename event.
 
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"error\":{\"previous\":\"NETWORK_FAILED\"},"
                          "  \"state\":{"
@@ -3441,7 +3438,7 @@ IN_PROC_BROWSER_TEST_F(
   FinishPendingSlowDownloads();
 
   // The download should complete successfully.
-  ASSERT_TRUE(WaitFor(events::kOnDownloadChanged,
+  ASSERT_TRUE(WaitFor(api::OnChanged::kEventName,
       base::StringPrintf("[{\"id\": %d,"
                          "  \"state\": {"
                          "    \"previous\": \"in_progress\","
diff --git a/chrome/browser/extensions/api/feedback_private/feedback_private_api.cc b/chrome/browser/extensions/api/feedback_private/feedback_private_api.cc
index b47bc53..fafcbd5 100644
--- a/chrome/browser/extensions/api/feedback_private/feedback_private_api.cc
+++ b/chrome/browser/extensions/api/feedback_private/feedback_private_api.cc
@@ -10,7 +10,6 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/api/feedback_private/feedback_service.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "grit/generated_resources.h"
@@ -20,8 +19,10 @@
 
 namespace extensions {
 
-using api::feedback_private::SystemInformation;
-using api::feedback_private::FeedbackInfo;
+namespace feedback_private = api::feedback_private;
+
+using feedback_private::SystemInformation;
+using feedback_private::FeedbackInfo;
 
 static base::LazyInstance<ProfileKeyedAPIFactory<FeedbackPrivateAPI> >
     g_factory = LAZY_INSTANCE_INITIALIZER;
@@ -68,8 +69,8 @@ void FeedbackPrivateAPI::RequestFeedback(
     scoped_ptr<base::ListValue> args(new base::ListValue());
     args->Append(info.ToValue().release());
 
-    scoped_ptr<Event> event(
-        new Event(event_names::kOnFeedbackRequested, args.Pass()));
+    scoped_ptr<Event> event(new Event(
+        feedback_private::OnFeedbackRequested::kEventName, args.Pass()));
     ExtensionSystem::Get(profile_)->event_router()->BroadcastEvent(
         event.Pass());
   }
@@ -122,14 +123,14 @@ bool FeedbackPrivateGetSystemInformationFunction::RunImpl() {
 
 void FeedbackPrivateGetSystemInformationFunction::OnCompleted(
     const SystemInformationList& sys_info) {
-  results_ = api::feedback_private::GetSystemInformation::Results::Create(
+  results_ = feedback_private::GetSystemInformation::Results::Create(
       sys_info);
   SendResponse(true);
 }
 
 bool FeedbackPrivateSendFeedbackFunction::RunImpl() {
-  scoped_ptr<api::feedback_private::SendFeedback::Params> params(
-      api::feedback_private::SendFeedback::Params::Create(*args_));
+  scoped_ptr<feedback_private::SendFeedback::Params> params(
+      feedback_private::SendFeedback::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
 
   const FeedbackInfo &feedback_info = params->feedback;
@@ -186,9 +187,9 @@ bool FeedbackPrivateSendFeedbackFunction::RunImpl() {
 
 void FeedbackPrivateSendFeedbackFunction::OnCompleted(
     bool success) {
-  results_ = api::feedback_private::SendFeedback::Results::Create(
-      success ? api::feedback_private::STATUS_SUCCESS :
-                api::feedback_private::STATUS_DELAYED);
+  results_ = feedback_private::SendFeedback::Results::Create(
+      success ? feedback_private::STATUS_SUCCESS :
+                feedback_private::STATUS_DELAYED);
   SendResponse(true);
 }
 
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 476adcb..2152270 100644
--- a/chrome/browser/extensions/api/font_settings/font_settings_api.cc
+++ b/chrome/browser/extensions/api/font_settings/font_settings_api.cc
@@ -49,14 +49,6 @@ const char kScriptKey[] = "script";
 const char kSetFromIncognitoError[] =
     "Can't modify regular settings from an incognito context.";
 
-const char kOnDefaultFixedFontSizeChanged[] =
-    "fontSettings.onDefaultFixedFontSizeChanged";
-const char kOnDefaultFontSizeChanged[] =
-    "fontSettings.onDefaultFontSizeChanged";
-const char kOnFontChanged[] = "fontSettings.onFontChanged";
-const char kOnMinimumFontSizeChanged[] =
-    "fontSettings.onMinimumFontSizeChanged";
-
 // Format for font name preference paths.
 const char kWebKitFontPrefFormat[] = "webkit.webprefs.fonts.%s.%s";
 
@@ -106,13 +98,13 @@ FontSettingsEventRouter::FontSettingsEventRouter(
   registrar_.Init(profile_->GetPrefs());
 
   AddPrefToObserve(prefs::kWebKitDefaultFixedFontSize,
-                   kOnDefaultFixedFontSizeChanged,
+                   fonts::OnDefaultFixedFontSizeChanged::kEventName,
                    kPixelSizeKey);
   AddPrefToObserve(prefs::kWebKitDefaultFontSize,
-                   kOnDefaultFontSizeChanged,
+                   fonts::OnDefaultFontSizeChanged::kEventName,
                    kPixelSizeKey);
   AddPrefToObserve(prefs::kWebKitMinimumFontSize,
-                   kOnMinimumFontSizeChanged,
+                   fonts::OnMinimumFontSizeChanged::kEventName,
                    kPixelSizeKey);
 
   PrefChangeRegistrar::NamedChangeCallback callback =
@@ -183,7 +175,7 @@ void FontSettingsEventRouter::OnFontNamePrefChanged(
 
   extensions::preference_helpers::DispatchEventToExtensions(
       profile_,
-      kOnFontChanged,
+      fonts::OnFontChanged::kEventName,
       &args,
       APIPermission::kFontSettings,
       false,
diff --git a/chrome/browser/extensions/api/history/history_api.cc b/chrome/browser/extensions/api/history/history_api.cc
index 0543a27..e387b4f 100644
--- a/chrome/browser/extensions/api/history/history_api.cc
+++ b/chrome/browser/extensions/api/history/history_api.cc
@@ -26,6 +26,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/cancelable_task_tracker.h"
 #include "chrome/common/extensions/api/experimental_history.h"
+#include "chrome/common/extensions/api/history.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_source.h"
@@ -52,9 +53,6 @@ namespace Search = api::history::Search;
 
 namespace {
 
-const char kOnVisited[] = "history.onVisited";
-const char kOnVisitRemoved[] = "history.onVisitRemoved";
-
 const char kInvalidIdError[] = "History item id is invalid.";
 const char kInvalidUrlError[] = "Url is invalid.";
 const char kDeleteProhibitedError[] = "Browsing history is not allowed to be "
@@ -170,7 +168,7 @@ void HistoryEventRouter::HistoryUrlVisited(
   scoped_ptr<HistoryItem> history_item = GetHistoryItem(details->row);
   scoped_ptr<base::ListValue> args = OnVisited::Create(*history_item);
 
-  DispatchEvent(profile, kOnVisited, args.Pass());
+  DispatchEvent(profile, api::history::OnVisited::kEventName, args.Pass());
 }
 
 void HistoryEventRouter::HistoryUrlsRemoved(
@@ -187,7 +185,7 @@ void HistoryEventRouter::HistoryUrlsRemoved(
   removed.urls.reset(urls);
 
   scoped_ptr<base::ListValue> args = OnVisitRemoved::Create(removed);
-  DispatchEvent(profile, kOnVisitRemoved, args.Pass());
+  DispatchEvent(profile, api::history::OnVisitRemoved::kEventName, args.Pass());
 }
 
 void HistoryEventRouter::DispatchEvent(
@@ -205,9 +203,9 @@ void HistoryEventRouter::DispatchEvent(
 
 HistoryAPI::HistoryAPI(Profile* profile) : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, kOnVisited);
+      this, api::history::OnVisited::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, kOnVisitRemoved);
+      this, api::history::OnVisitRemoved::kEventName);
 }
 
 HistoryAPI::~HistoryAPI() {
diff --git a/chrome/browser/extensions/api/identity/web_auth_flow.cc b/chrome/browser/extensions/api/identity/web_auth_flow.cc
index 977f1f1..2c50724 100644
--- a/chrome/browser/extensions/api/identity/web_auth_flow.cc
+++ b/chrome/browser/extensions/api/identity/web_auth_flow.cc
@@ -16,6 +16,7 @@
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/identity_private.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
@@ -38,6 +39,8 @@ using content::WebContentsObserver;
 
 namespace extensions {
 
+namespace identity_private = api::identity_private;
+
 WebAuthFlow::WebAuthFlow(
     Delegate* delegate,
     Profile* profile,
@@ -86,7 +89,7 @@ void WebAuthFlow::Start() {
     args->AppendString("silent");
 
   scoped_ptr<Event> event(
-      new Event("identityPrivate.onWebFlowRequest", args.Pass()));
+      new Event(identity_private::OnWebFlowRequest::kEventName, args.Pass()));
   event->restrict_to_profile = profile_;
   ExtensionSystem* system = ExtensionSystem::Get(profile_);
 
diff --git a/chrome/browser/extensions/api/idle/idle_api_constants.cc b/chrome/browser/extensions/api/idle/idle_api_constants.cc
index 15d6325..84d42e0 100644
--- a/chrome/browser/extensions/api/idle/idle_api_constants.cc
+++ b/chrome/browser/extensions/api/idle/idle_api_constants.cc
@@ -8,8 +8,6 @@ namespace extensions {
 
 namespace idle_api_constants {
 
-const char kOnStateChanged[] = "idle.onStateChanged";
-
 const char kStateActive[] = "active";
 const char kStateIdle[] = "idle";
 const char kStateLocked[] = "locked";
diff --git a/chrome/browser/extensions/api/idle/idle_api_unittest.cc b/chrome/browser/extensions/api/idle/idle_api_unittest.cc
index bbffd00..cf6ee66 100644
--- a/chrome/browser/extensions/api/idle/idle_api_unittest.cc
+++ b/chrome/browser/extensions/api/idle/idle_api_unittest.cc
@@ -14,6 +14,7 @@
 #include "chrome/browser/extensions/api/idle/idle_manager_factory.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_function_test_utils.h"
+#include "chrome/common/extensions/api/idle.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/test/base/browser_with_test_window_test.h"
@@ -25,6 +26,7 @@
 using ::testing::_;
 
 namespace utils = extension_function_test_utils;
+namespace idle = extensions::api::idle;
 
 namespace extensions {
 
@@ -107,13 +109,13 @@ ScopedListen::ScopedListen(IdleManager* idle_manager,
                            const std::string& extension_id)
     : idle_manager_(idle_manager),
       extension_id_(extension_id) {
-  const EventListenerInfo details(idle_api_constants::kOnStateChanged,
+  const EventListenerInfo details(idle::OnStateChanged::kEventName,
                                   extension_id_);
   idle_manager_->OnListenerAdded(details);
 }
 
 ScopedListen::~ScopedListen() {
-  const EventListenerInfo details(idle_api_constants::kOnStateChanged,
+  const EventListenerInfo details(idle::OnStateChanged::kEventName,
                                   extension_id_);
   idle_manager_->OnListenerRemoved(details);
 }
diff --git a/chrome/browser/extensions/api/idle/idle_manager.cc b/chrome/browser/extensions/api/idle/idle_manager.cc
index 8b66e86..48785c7 100644
--- a/chrome/browser/extensions/api/idle/idle_manager.cc
+++ b/chrome/browser/extensions/api/idle/idle_manager.cc
@@ -12,12 +12,14 @@
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/idle.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_source.h"
 
 namespace keys = extensions::idle_api_constants;
+namespace idle = extensions::api::idle;
 
 namespace extensions {
 
@@ -51,7 +53,8 @@ void DefaultEventDelegate::OnStateChanged(const std::string& extension_id,
                                           IdleState new_state) {
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(IdleManager::CreateIdleValue(new_state));
-  scoped_ptr<Event> event(new Event(keys::kOnStateChanged, args.Pass()));
+  scoped_ptr<Event> event(new Event(idle::OnStateChanged::kEventName,
+                                    args.Pass()));
   event->restrict_to_profile = profile_;
   ExtensionSystem::Get(profile_)->event_router()->DispatchEventToExtension(
       extension_id, event.Pass());
@@ -60,7 +63,7 @@ void DefaultEventDelegate::OnStateChanged(const std::string& extension_id,
 void DefaultEventDelegate::RegisterObserver(
     EventRouter::Observer* observer) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      observer, idle_api_constants::kOnStateChanged);
+      observer, idle::OnStateChanged::kEventName);
 }
 
 void DefaultEventDelegate::UnregisterObserver(EventRouter::Observer* observer) {
diff --git a/chrome/browser/extensions/api/input_ime/input_ime_api.cc b/chrome/browser/extensions/api/input_ime/input_ime_api.cc
index 20d89e6..15baf4b 100644
--- a/chrome/browser/extensions/api/input_ime/input_ime_api.cc
+++ b/chrome/browser/extensions/api/input_ime/input_ime_api.cc
@@ -79,21 +79,6 @@ static void DispatchEventToExtension(Profile* profile,
 
 }  // namespace
 
-namespace events {
-
-const char kOnActivate[] = "input.ime.onActivate";
-const char kOnDeactivated[] = "input.ime.onDeactivated";
-const char kOnFocus[] = "input.ime.onFocus";
-const char kOnBlur[] = "input.ime.onBlur";
-const char kOnInputContextUpdate[] = "input.ime.onInputContextUpdate";
-const char kOnKeyEvent[] = "input.ime.onKeyEvent";
-const char kOnCandidateClicked[] = "input.ime.onCandidateClicked";
-const char kOnMenuItemActivated[] = "input.ime.onMenuItemActivated";
-const char kOnSurroundingTextChanged[] = "input.ime.onSurroundingTextChanged";
-const char kOnReset[] = "input.ime.onReset";
-
-}  // namespace events
-
 namespace chromeos {
 class ImeObserver : public chromeos::InputMethodEngine::Observer {
  public:
@@ -114,7 +99,7 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(new base::StringValue(engine_id));
 
     DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnActivate, args.Pass());
+                             input_ime::OnActivate::kEventName, args.Pass());
   }
 
   virtual void OnDeactivated(const std::string& engine_id) OVERRIDE {
@@ -125,7 +110,7 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(new base::StringValue(engine_id));
 
     DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnDeactivated, args.Pass());
+                             input_ime::OnDeactivated::kEventName, args.Pass());
   }
 
   virtual void OnFocus(
@@ -141,7 +126,7 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(dict);
 
     DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnFocus, args.Pass());
+                             input_ime::OnFocus::kEventName, args.Pass());
   }
 
   virtual void OnBlur(int context_id) OVERRIDE {
@@ -152,7 +137,7 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(new base::FundamentalValue(context_id));
 
     DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnBlur, args.Pass());
+                             input_ime::OnBlur::kEventName, args.Pass());
   }
 
   virtual void OnInputContextUpdate(
@@ -167,8 +152,10 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     scoped_ptr<base::ListValue> args(new base::ListValue());
     args->Append(dict);
 
-    DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnInputContextUpdate, args.Pass());
+    DispatchEventToExtension(profile_,
+                             extension_id_,
+                             input_ime::OnInputContextUpdate::kEventName,
+                             args.Pass());
   }
 
   virtual void OnKeyEvent(
@@ -197,7 +184,7 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(dict);
 
     DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnKeyEvent, args.Pass());
+                             input_ime::OnKeyEvent::kEventName, args.Pass());
   }
 
   virtual void OnCandidateClicked(
@@ -226,8 +213,10 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
         break;
     }
 
-    DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnCandidateClicked, args.Pass());
+    DispatchEventToExtension(profile_,
+                             extension_id_,
+                             input_ime::OnCandidateClicked::kEventName,
+                             args.Pass());
   }
 
   virtual void OnMenuItemActivated(const std::string& engine_id,
@@ -239,8 +228,10 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(new base::StringValue(engine_id));
     args->Append(new base::StringValue(menu_id));
 
-    DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnMenuItemActivated, args.Pass());
+    DispatchEventToExtension(profile_,
+                             extension_id_,
+                             input_ime::OnMenuItemActivated::kEventName,
+                             args.Pass());
   }
 
   virtual void OnSurroundingTextChanged(const std::string& engine_id,
@@ -258,8 +249,10 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     args->Append(new base::StringValue(engine_id));
     args->Append(dict);
 
-    DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnSurroundingTextChanged, args.Pass());
+    DispatchEventToExtension(profile_,
+                             extension_id_,
+                             input_ime::OnSurroundingTextChanged::kEventName,
+                             args.Pass());
   }
 
   virtual void OnReset(const std::string& engine_id) OVERRIDE {
@@ -268,8 +261,10 @@ class ImeObserver : public chromeos::InputMethodEngine::Observer {
     scoped_ptr<base::ListValue> args(new base::ListValue());
     args->Append(new base::StringValue(engine_id));
 
-    DispatchEventToExtension(profile_, extension_id_,
-                             events::kOnReset, args.Pass());
+    DispatchEventToExtension(profile_,
+                             extension_id_,
+                             input_ime::OnReset::kEventName,
+                             args.Pass());
   }
 
  private:
diff --git a/chrome/browser/extensions/api/location/location_manager.cc b/chrome/browser/extensions/api/location/location_manager.cc
index 5611a43..95579a3 100644
--- a/chrome/browser/extensions/api/location/location_manager.cc
+++ b/chrome/browser/extensions/api/location/location_manager.cc
@@ -382,12 +382,12 @@ void LocationManager::SendLocationUpdate(
     location.timestamp = position.timestamp.ToJsTime();
 
     args->Append(location.ToValue().release());
-    event_name = "location.onLocationUpdate";
+    event_name = location::OnLocationUpdate::kEventName;
   } else {
     // Set data for onLocationError event.
     // TODO(vadimt): Set name.
     args->AppendString(position.error_message);
-    event_name = "location.onLocationError";
+    event_name = location::OnLocationError::kEventName;
   }
 
   scoped_ptr<Event> event(new Event(event_name, args.Pass()));
diff --git a/chrome/browser/extensions/api/management/management_api.cc b/chrome/browser/extensions/api/management/management_api.cc
index 1debb52..eb776d1 100644
--- a/chrome/browser/extensions/api/management/management_api.cc
+++ b/chrome/browser/extensions/api/management/management_api.cc
@@ -20,7 +20,6 @@
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/extensions/api/management/management_api_constants.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -60,7 +59,6 @@ namespace keys = extension_management_api_constants;
 
 namespace extensions {
 
-namespace events = event_names;
 namespace management = api::management;
 
 namespace {
@@ -652,20 +650,20 @@ void ManagementEventRouter::Observe(
 
   switch (type) {
     case chrome::NOTIFICATION_EXTENSION_INSTALLED:
-      event_name = events::kOnExtensionInstalled;
+      event_name = management::OnInstalled::kEventName;
       extension =
           content::Details<const InstalledExtensionInfo>(details)->extension;
       break;
     case chrome::NOTIFICATION_EXTENSION_UNINSTALLED:
-      event_name = events::kOnExtensionUninstalled;
+      event_name = management::OnUninstalled::kEventName;
       extension = content::Details<const Extension>(details).ptr();
       break;
     case chrome::NOTIFICATION_EXTENSION_LOADED:
-      event_name = events::kOnExtensionEnabled;
+      event_name = management::OnEnabled::kEventName;
       extension = content::Details<const Extension>(details).ptr();
       break;
     case chrome::NOTIFICATION_EXTENSION_UNLOADED:
-      event_name = events::kOnExtensionDisabled;
+      event_name = management::OnDisabled::kEventName;
       extension =
           content::Details<const UnloadedExtensionInfo>(details)->extension;
       break;
@@ -680,7 +678,7 @@ void ManagementEventRouter::Observe(
     return; // Don't dispatch events for built-in extensions.
 
   scoped_ptr<base::ListValue> args(new base::ListValue());
-  if (event_name == events::kOnExtensionUninstalled) {
+  if (event_name == management::OnUninstalled::kEventName) {
     args->Append(new base::StringValue(extension->id()));
   } else {
     scoped_ptr<management::ExtensionInfo> info = CreateExtensionInfo(
@@ -695,13 +693,13 @@ void ManagementEventRouter::Observe(
 ManagementAPI::ManagementAPI(Profile* profile)
     : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, events::kOnExtensionInstalled);
+      this, management::OnInstalled::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, events::kOnExtensionUninstalled);
+      this, management::OnUninstalled::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, events::kOnExtensionEnabled);
+      this, management::OnEnabled::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, events::kOnExtensionDisabled);
+      this, management::OnDisabled::kEventName);
 }
 
 ManagementAPI::~ManagementAPI() {
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.cc b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.cc
index 7e8436cc..4111d0c 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.cc
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.cc
@@ -40,6 +40,8 @@ namespace GetAllGalleryWatch =
     extensions::api::media_galleries_private::GetAllGalleryWatch;
 namespace EjectDevice =
     extensions::api::media_galleries_private::EjectDevice;
+namespace media_galleries_private =
+    api::media_galleries_private;
 
 namespace {
 
@@ -87,11 +89,11 @@ MediaGalleriesPrivateAPI::MediaGalleriesPrivateAPI(Profile* profile)
       weak_ptr_factory_(this) {
   DCHECK(profile_);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnAttachEventName);
+      this, media_galleries_private::OnDeviceAttached::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnDetachEventName);
+      this, media_galleries_private::OnDeviceDetached::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnGalleryChangedEventName);
+      this, media_galleries_private::OnGalleryChanged::kEventName);
 }
 
 MediaGalleriesPrivateAPI::~MediaGalleriesPrivateAPI() {
@@ -217,7 +219,7 @@ void MediaGalleriesPrivateAddGalleryWatchFunction::HandleResponse(
     chrome::MediaGalleryPrefId gallery_id,
     bool success) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
-  extensions::api::media_galleries_private::AddGalleryWatchResult result;
+  media_galleries_private::AddGalleryWatchResult result;
   result.gallery_id = base::Uint64ToString(gallery_id);
   result.success = success;
   SetResult(result.ToValue().release());
@@ -396,15 +398,11 @@ void MediaGalleriesPrivateEjectDeviceFunction::OnStorageMonitorInit(
 
 void MediaGalleriesPrivateEjectDeviceFunction::HandleResponse(
     chrome::StorageMonitor::EjectStatus status) {
-  using extensions::api::media_galleries_private::
-      EJECT_DEVICE_RESULT_CODE_FAILURE;
-  using extensions::api::media_galleries_private::
-      EJECT_DEVICE_RESULT_CODE_IN_USE;
-  using extensions::api::media_galleries_private::
-      EJECT_DEVICE_RESULT_CODE_NO_SUCH_DEVICE;
-  using extensions::api::media_galleries_private::
-      EJECT_DEVICE_RESULT_CODE_SUCCESS;
-  using extensions::api::media_galleries_private::EjectDeviceResultCode;
+  using media_galleries_private::EJECT_DEVICE_RESULT_CODE_FAILURE;
+  using media_galleries_private::EJECT_DEVICE_RESULT_CODE_IN_USE;
+  using media_galleries_private::EJECT_DEVICE_RESULT_CODE_NO_SUCH_DEVICE;
+  using media_galleries_private::EJECT_DEVICE_RESULT_CODE_SUCCESS;
+  using media_galleries_private::EjectDeviceResultCode;
 
   EjectDeviceResultCode result = EJECT_DEVICE_RESULT_CODE_FAILURE;
   if (status == chrome::StorageMonitor::EJECT_OK)
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
index 2522239..8f0baf3 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.cc
@@ -18,6 +18,8 @@
 #include "chrome/common/extensions/api/media_galleries_private.h"
 #include "content/public/browser/browser_thread.h"
 
+namespace media_galleries_private = extensions::api::media_galleries_private;
+
 namespace extensions {
 
 namespace {
@@ -29,9 +31,9 @@ std::string GetTransientIdForDeviceId(const std::string& device_id) {
 
 }  // namespace
 
-using extensions::api::media_galleries_private::DeviceAttachmentDetails;
-using extensions::api::media_galleries_private::DeviceDetachmentDetails;
-using extensions::api::media_galleries_private::GalleryChangeDetails;
+using media_galleries_private::DeviceAttachmentDetails;
+using media_galleries_private::DeviceDetachmentDetails;
+using media_galleries_private::GalleryChangeDetails;
 
 MediaGalleriesPrivateEventRouter::MediaGalleriesPrivateEventRouter(
     Profile* profile)
@@ -55,7 +57,8 @@ void MediaGalleriesPrivateEventRouter::OnGalleryChanged(
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   EventRouter* router =
       extensions::ExtensionSystem::Get(profile_)->event_router();
-  if (!router->HasEventListener(event_names::kOnGalleryChangedEventName))
+  if (!router->HasEventListener(
+          media_galleries_private::OnGalleryChanged::kEventName))
     return;
 
   for (std::set<std::string>::const_iterator it = extension_ids.begin();
@@ -65,7 +68,7 @@ void MediaGalleriesPrivateEventRouter::OnGalleryChanged(
     scoped_ptr<base::ListValue> args(new base::ListValue());
     args->Append(details.ToValue().release());
     scoped_ptr<extensions::Event> event(new extensions::Event(
-        event_names::kOnGalleryChangedEventName,
+        media_galleries_private::OnGalleryChanged::kEventName,
         args.Pass()));
     // Use DispatchEventToExtension() instead of BroadcastEvent().
     // BroadcastEvent() sends the gallery changed events to all the extensions
@@ -83,7 +86,8 @@ void MediaGalleriesPrivateEventRouter::OnRemovableStorageAttached(
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   EventRouter* router =
       extensions::ExtensionSystem::Get(profile_)->event_router();
-  if (!router->HasEventListener(event_names::kOnAttachEventName))
+  if (!router->HasEventListener(
+          media_galleries_private::OnDeviceAttached::kEventName))
     return;
 
   chrome::MediaGalleryPrefInfo pref_info;
@@ -102,7 +106,8 @@ void MediaGalleriesPrivateEventRouter::OnRemovableStorageAttached(
 
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(details.ToValue().release());
-  DispatchEvent(event_names::kOnAttachEventName, args.Pass());
+  DispatchEvent(
+      media_galleries_private::OnDeviceAttached::kEventName, args.Pass());
 }
 
 void MediaGalleriesPrivateEventRouter::OnRemovableStorageDetached(
@@ -110,7 +115,8 @@ void MediaGalleriesPrivateEventRouter::OnRemovableStorageDetached(
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   EventRouter* router =
       extensions::ExtensionSystem::Get(profile_)->event_router();
-  if (!router->HasEventListener(event_names::kOnDetachEventName))
+  if (!router->HasEventListener(
+          media_galleries_private::OnDeviceDetached::kEventName))
     return;
 
   DeviceDetachmentDetails details;
@@ -118,7 +124,8 @@ void MediaGalleriesPrivateEventRouter::OnRemovableStorageDetached(
 
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(details.ToValue().release());
-  DispatchEvent(event_names::kOnDetachEventName, args.Pass());
+  DispatchEvent(
+      media_galleries_private::OnDeviceDetached::kEventName, args.Pass());
 }
 
 void MediaGalleriesPrivateEventRouter::DispatchEvent(
diff --git a/chrome/browser/extensions/api/networking_private/networking_private_api_nonchromeos.cc b/chrome/browser/extensions/api/networking_private/networking_private_api_nonchromeos.cc
index 65ddc026..15adc7a 100644
--- a/chrome/browser/extensions/api/networking_private/networking_private_api_nonchromeos.cc
+++ b/chrome/browser/extensions/api/networking_private/networking_private_api_nonchromeos.cc
@@ -10,7 +10,6 @@
 #include "base/command_line.h"
 #include "base/json/json_reader.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_function_registry.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -18,8 +17,6 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/api/networking_private.h"
 
-using extensions::event_names::kOnNetworkListChanged;
-using extensions::event_names::kOnNetworksChanged;
 using extensions::EventRouter;
 using extensions::ExtensionSystem;
 namespace api = extensions::api::networking_private;
@@ -289,7 +286,7 @@ bool NetworkingPrivateRequestNetworkScanFunction::RunImpl() {
   EventRouter* event_router = ExtensionSystem::Get(profile_)->event_router();
   scoped_ptr<base::ListValue> args(api::OnNetworkListChanged::Create(changes));
   scoped_ptr<extensions::Event> extension_event(new extensions::Event(
-      kOnNetworkListChanged, args.Pass()));
+      api::OnNetworkListChanged::kEventName, args.Pass()));
   event_router->BroadcastEvent(extension_event.Pass());
 
   return true;
@@ -333,7 +330,7 @@ bool NetworkingPrivateStartConnectFunction::RunImpl() {
     scoped_ptr<base::ListValue> args(api::OnNetworksChanged::Create(
         std::vector<std::string>(1, params->network_guid)));
     scoped_ptr<extensions::Event> netchanged_event(
-        new extensions::Event(kOnNetworksChanged, args.Pass()));
+        new extensions::Event(api::OnNetworksChanged::kEventName, args.Pass()));
     event_router->BroadcastEvent(netchanged_event.Pass());
 
     // Generate NetworkListChanged event.
@@ -346,7 +343,7 @@ bool NetworkingPrivateStartConnectFunction::RunImpl() {
 
     scoped_ptr<base::ListValue> arg2(api::OnNetworkListChanged::Create(list));
     scoped_ptr<extensions::Event> netlist_event(new extensions::Event(
-        kOnNetworkListChanged, arg2.Pass()));
+        api::OnNetworkListChanged::kEventName, arg2.Pass()));
     event_router->BroadcastEvent(netlist_event.Pass());
   }
   return true;
@@ -374,7 +371,7 @@ bool NetworkingPrivateStartDisconnectFunction::RunImpl() {
     scoped_ptr<base::ListValue> args(api::OnNetworksChanged::Create(
         std::vector<std::string>(1, params->network_guid)));
     scoped_ptr<extensions::Event> extension_event(
-        new extensions::Event(kOnNetworksChanged, args.Pass()));
+        new extensions::Event(api::OnNetworksChanged::kEventName, args.Pass()));
     event_router->BroadcastEvent(extension_event.Pass());
   }
   return true;
diff --git a/chrome/browser/extensions/api/networking_private/networking_private_event_router_chromeos.cc b/chrome/browser/extensions/api/networking_private/networking_private_event_router_chromeos.cc
index 44d70eb..c431c7f 100644
--- a/chrome/browser/extensions/api/networking_private/networking_private_event_router_chromeos.cc
+++ b/chrome/browser/extensions/api/networking_private/networking_private_event_router_chromeos.cc
@@ -7,7 +7,6 @@
 #include "base/json/json_writer.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/api/networking_private/networking_private_api.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_system_factory.h"
@@ -22,8 +21,6 @@
 #include "components/browser_context_keyed_service/browser_context_dependency_manager.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
-using extensions::event_names::kOnNetworkListChanged;
-using extensions::event_names::kOnNetworksChanged;
 using extensions::EventRouter;
 using extensions::ExtensionSystem;
 namespace api = extensions::api::networking_private;
@@ -39,9 +36,9 @@ NetworkingPrivateEventRouter::NetworkingPrivateEventRouter(Profile* profile)
   EventRouter* event_router = ExtensionSystem::Get(profile_)->event_router();
   if (event_router) {
     event_router->RegisterObserver(
-        this, extensions::event_names::kOnNetworksChanged);
+        this, api::OnNetworksChanged::kEventName);
     event_router->RegisterObserver(
-        this, extensions::event_names::kOnNetworkListChanged);
+        this, api::OnNetworkListChanged::kEventName);
     StartOrStopListeningForNetworkChanges();
   }
 }
@@ -80,8 +77,9 @@ void NetworkingPrivateEventRouter::OnListenerRemoved(
 
 void NetworkingPrivateEventRouter::StartOrStopListeningForNetworkChanges() {
   EventRouter* event_router = ExtensionSystem::Get(profile_)->event_router();
-  bool should_listen = event_router->HasEventListener(kOnNetworksChanged) ||
-      event_router->HasEventListener(kOnNetworkListChanged);
+  bool should_listen =
+      event_router->HasEventListener(api::OnNetworksChanged::kEventName) ||
+      event_router->HasEventListener(api::OnNetworkListChanged::kEventName);
 
   if (should_listen && !listening_) {
     NetworkHandler::Get()->network_state_handler()->AddObserver(
@@ -97,7 +95,7 @@ void NetworkingPrivateEventRouter::NetworkListChanged() {
   EventRouter* event_router = ExtensionSystem::Get(profile_)->event_router();
   NetworkStateHandler::NetworkStateList networks;
   NetworkHandler::Get()->network_state_handler()->GetNetworkList(&networks);
-  if (!event_router->HasEventListener(kOnNetworkListChanged)) {
+  if (!event_router->HasEventListener(api::OnNetworkListChanged::kEventName)) {
     // TODO(stevenjb): Remove logging once crbug.com/256881 is fixed
     // (or at least reduce to LOG_DEBUG). Same with NET_LOG events below.
     NET_LOG_EVENT("NetworkingPrivate.NetworkListChanged: No Listeners", "");
@@ -117,14 +115,14 @@ void NetworkingPrivateEventRouter::NetworkListChanged() {
 
   scoped_ptr<base::ListValue> args(api::OnNetworkListChanged::Create(changes));
   scoped_ptr<extensions::Event> extension_event(new extensions::Event(
-      kOnNetworkListChanged, args.Pass()));
+      api::OnNetworkListChanged::kEventName, args.Pass()));
   event_router->BroadcastEvent(extension_event.Pass());
 }
 
 void NetworkingPrivateEventRouter::NetworkPropertiesUpdated(
     const NetworkState* network) {
   EventRouter* event_router = ExtensionSystem::Get(profile_)->event_router();
-  if (!event_router->HasEventListener(kOnNetworksChanged)) {
+  if (!event_router->HasEventListener(api::OnNetworksChanged::kEventName)) {
     NET_LOG_EVENT("NetworkingPrivate.NetworkPropertiesUpdated: No Listeners",
                   network->path());
     return;
@@ -134,7 +132,7 @@ void NetworkingPrivateEventRouter::NetworkPropertiesUpdated(
   scoped_ptr<base::ListValue> args(api::OnNetworksChanged::Create(
       std::vector<std::string>(1, network->path())));
   scoped_ptr<extensions::Event> extension_event(
-      new extensions::Event(kOnNetworksChanged, args.Pass()));
+      new extensions::Event(api::OnNetworksChanged::kEventName, args.Pass()));
   event_router->BroadcastEvent(extension_event.Pass());
 }
 
diff --git a/chrome/browser/extensions/api/notifications/notifications_api.cc b/chrome/browser/extensions/api/notifications/notifications_api.cc
index 962e162..c69f4cb 100644
--- a/chrome/browser/extensions/api/notifications/notifications_api.cc
+++ b/chrome/browser/extensions/api/notifications/notifications_api.cc
@@ -32,6 +32,8 @@
 
 namespace extensions {
 
+namespace notifications = api::notifications;
+
 namespace {
 
 const char kResultKey[] = "result";
@@ -150,23 +152,23 @@ class NotificationsApiDelegate : public NotificationDelegate {
   virtual void Close(bool by_user) OVERRIDE {
     scoped_ptr<base::ListValue> args(CreateBaseEventArgs());
     args->Append(new base::FundamentalValue(by_user));
-    SendEvent(event_names::kOnNotificationClosed, args.Pass());
+    SendEvent(notifications::OnClosed::kEventName, args.Pass());
   }
 
   virtual void Click() OVERRIDE {
     scoped_ptr<base::ListValue> args(CreateBaseEventArgs());
-    SendEvent(event_names::kOnNotificationClicked, args.Pass());
+    SendEvent(notifications::OnClicked::kEventName, args.Pass());
   }
 
   virtual bool HasClickedListener() OVERRIDE {
     return ExtensionSystem::Get(profile_)->event_router()->HasEventListener(
-        event_names::kOnNotificationClicked);
+        notifications::OnClicked::kEventName);
   }
 
   virtual void ButtonClick(int index) OVERRIDE {
     scoped_ptr<base::ListValue> args(CreateBaseEventArgs());
     args->Append(new base::FundamentalValue(index));
-    SendEvent(event_names::kOnNotificationButtonClicked, args.Pass());
+    SendEvent(notifications::OnButtonClicked::kEventName, args.Pass());
   }
 
   virtual std::string id() const OVERRIDE {
diff --git a/chrome/browser/extensions/api/omnibox/omnibox_api.cc b/chrome/browser/extensions/api/omnibox/omnibox_api.cc
index 18250ad..585b39e 100644
--- a/chrome/browser/extensions/api/omnibox/omnibox_api.cc
+++ b/chrome/browser/extensions/api/omnibox/omnibox_api.cc
@@ -27,13 +27,6 @@
 #include "content/public/browser/notification_service.h"
 #include "ui/gfx/image/image.h"
 
-namespace events {
-const char kOnInputStarted[] = "omnibox.onInputStarted";
-const char kOnInputChanged[] = "omnibox.onInputChanged";
-const char kOnInputEntered[] = "omnibox.onInputEntered";
-const char kOnInputCancelled[] = "omnibox.onInputCancelled";
-}  // namespace events
-
 namespace extensions {
 
 namespace omnibox = api::omnibox;
@@ -112,7 +105,8 @@ bool SetOmniboxDefaultSuggestion(
 void ExtensionOmniboxEventRouter::OnInputStarted(
     Profile* profile, const std::string& extension_id) {
   scoped_ptr<Event> event(new Event(
-      events::kOnInputStarted, make_scoped_ptr(new base::ListValue())));
+      omnibox::OnInputStarted::kEventName,
+      make_scoped_ptr(new base::ListValue())));
   event->restrict_to_profile = profile;
   ExtensionSystem::Get(profile)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
@@ -123,14 +117,16 @@ bool ExtensionOmniboxEventRouter::OnInputChanged(
     Profile* profile, const std::string& extension_id,
     const std::string& input, int suggest_id) {
   if (!extensions::ExtensionSystem::Get(profile)->event_router()->
-          ExtensionHasEventListener(extension_id, events::kOnInputChanged))
+          ExtensionHasEventListener(extension_id,
+                                    omnibox::OnInputChanged::kEventName))
     return false;
 
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Set(0, new base::StringValue(input));
   args->Set(1, new base::FundamentalValue(suggest_id));
 
-  scoped_ptr<Event> event(new Event(events::kOnInputChanged, args.Pass()));
+  scoped_ptr<Event> event(new Event(omnibox::OnInputChanged::kEventName,
+                                    args.Pass()));
   event->restrict_to_profile = profile;
   ExtensionSystem::Get(profile)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
@@ -162,7 +158,8 @@ void ExtensionOmniboxEventRouter::OnInputEntered(
   else
     args->Set(1, new base::StringValue(kCurrentTabDisposition));
 
-  scoped_ptr<Event> event(new Event(events::kOnInputEntered, args.Pass()));
+  scoped_ptr<Event> event(new Event(omnibox::OnInputEntered::kEventName,
+                                    args.Pass()));
   event->restrict_to_profile = profile;
   ExtensionSystem::Get(profile)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
@@ -177,7 +174,8 @@ void ExtensionOmniboxEventRouter::OnInputEntered(
 void ExtensionOmniboxEventRouter::OnInputCancelled(
     Profile* profile, const std::string& extension_id) {
   scoped_ptr<Event> event(new Event(
-      events::kOnInputCancelled, make_scoped_ptr(new base::ListValue())));
+      omnibox::OnInputCancelled::kEventName,
+      make_scoped_ptr(new base::ListValue())));
   event->restrict_to_profile = profile;
   ExtensionSystem::Get(profile)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
diff --git a/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc b/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
index 5cc854f..d9fdf77 100644
--- a/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
+++ b/chrome/browser/extensions/api/push_messaging/push_messaging_api.cc
@@ -13,7 +13,6 @@
 #include "base/values.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/extensions/api/push_messaging/push_messaging_invalidation_handler.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -78,7 +77,7 @@ void PushMessagingEventRouter::OnMessage(const std::string& extension_id,
 
   scoped_ptr<base::ListValue> args(glue::OnMessage::Create(message));
   scoped_ptr<extensions::Event> event(new extensions::Event(
-      event_names::kOnPushMessage, args.Pass()));
+      glue::OnMessage::kEventName, args.Pass()));
   event->restrict_to_profile = profile_;
   ExtensionSystem::Get(profile_)->event_router()->DispatchEventToExtension(
       extension_id, event.Pass());
diff --git a/chrome/browser/extensions/api/recovery_private/recovery_operation_manager.cc b/chrome/browser/extensions/api/recovery_private/recovery_operation_manager.cc
index 3c80583..3bf999e 100644
--- a/chrome/browser/extensions/api/recovery_private/recovery_operation_manager.cc
+++ b/chrome/browser/extensions/api/recovery_private/recovery_operation_manager.cc
@@ -8,7 +8,6 @@
 #include "chrome/browser/extensions/api/recovery_private/recovery_operation_manager.h"
 #include "chrome/browser/extensions/api/recovery_private/write_from_file_operation.h"
 #include "chrome/browser/extensions/api/recovery_private/write_from_url_operation.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -17,6 +16,9 @@
 #include "content/public/browser/notification_service.h"
 
 namespace extensions {
+
+namespace recovery_private = extensions::api::recovery_private;
+
 namespace recovery {
 
 namespace {
@@ -112,8 +114,8 @@ void RecoveryOperationManager::OnProgress(const ExtensionId& extension_id,
   info.percent_complete = progress;
 
   scoped_ptr<base::ListValue> args(recovery_api::OnWriteProgress::Create(info));
-  scoped_ptr<Event> event(new Event(event_names::kRecoveryOnWriteProgress,
-                                    args.Pass()));
+  scoped_ptr<Event> event(new Event(
+      recovery_private::OnWriteProgress::kEventName, args.Pass()));
 
   ExtensionSystem::Get(profile_)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
@@ -122,8 +124,8 @@ void RecoveryOperationManager::OnProgress(const ExtensionId& extension_id,
 void RecoveryOperationManager::OnComplete(const ExtensionId& extension_id) {
 
   scoped_ptr<base::ListValue> args(recovery_api::OnWriteComplete::Create());
-  scoped_ptr<Event> event(new Event(event_names::kRecoveryOnWriteComplete,
-                                    args.Pass()));
+  scoped_ptr<Event> event(new Event(
+      recovery_private::OnWriteComplete::kEventName, args.Pass()));
 
   ExtensionSystem::Get(profile_)->event_router()->
       DispatchEventToExtension(extension_id, event.Pass());
@@ -140,7 +142,7 @@ void RecoveryOperationManager::OnError(const ExtensionId& extension_id,
   info.percent_complete = progress;
 
   scoped_ptr<base::ListValue> args(recovery_api::OnWriteError::Create(info));
-  scoped_ptr<Event> event(new Event(event_names::kRecoveryOnWriteError,
+  scoped_ptr<Event> event(new Event(recovery_private::OnWriteError::kEventName,
                                     args.Pass()));
 
   ExtensionSystem::Get(profile_)->event_router()->
diff --git a/chrome/browser/extensions/api/rtc_private/rtc_private_api.cc b/chrome/browser/extensions/api/rtc_private/rtc_private_api.cc
index ac1fe83..2fe759d 100644
--- a/chrome/browser/extensions/api/rtc_private/rtc_private_api.cc
+++ b/chrome/browser/extensions/api/rtc_private/rtc_private_api.cc
@@ -30,10 +30,10 @@ using contacts::Contact_PhoneNumber;
 
 namespace extensions {
 
+namespace rtc_private = api::rtc_private;
+
 namespace {
 
-// Launch event name.
-const char kOnLaunchEvent[] = "rtcPrivate.onLaunch";
 // Web intent data payload mimetype.
 const char kMimeTypeJson[] = "application/vnd.chromium.contact";
 // Web intent data structure fields.
@@ -92,7 +92,7 @@ void RtcPrivateEventRouter::DispatchLaunchEvent(
     Profile* profile, LaunchAction action, const Contact* contact) {
   if (action == RtcPrivateEventRouter::LAUNCH_ACTIVATE) {
     scoped_ptr<Event> event(new Event(
-        kOnLaunchEvent, make_scoped_ptr(new ListValue())));
+        rtc_private::OnLaunch::kEventName, make_scoped_ptr(new ListValue())));
     event->restrict_to_profile = profile;
     ExtensionSystem::Get(profile)->event_router()->BroadcastEvent(event.Pass());
   } else {
@@ -103,7 +103,8 @@ void RtcPrivateEventRouter::DispatchLaunchEvent(
                          &launch_data.intent.data.additional_properties);
     launch_data.intent.type = kMimeTypeJson;
     scoped_ptr<Event> event(new Event(
-        kOnLaunchEvent, api::rtc_private::OnLaunch::Create(launch_data)));
+        rtc_private::OnLaunch::kEventName,
+        api::rtc_private::OnLaunch::Create(launch_data)));
     event->restrict_to_profile = profile;
     ExtensionSystem::Get(profile)->event_router()->BroadcastEvent(event.Pass());
   }
diff --git a/chrome/browser/extensions/api/runtime/runtime_api.cc b/chrome/browser/extensions/api/runtime/runtime_api.cc
index e54664e..5966e8a 100644
--- a/chrome/browser/extensions/api/runtime/runtime_api.cc
+++ b/chrome/browser/extensions/api/runtime/runtime_api.cc
@@ -23,6 +23,7 @@
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/browser_window.h"
+#include "chrome/common/extensions/api/runtime.h"
 #include "chrome/common/extensions/background_info.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/omaha_query_params/omaha_query_params.h"
@@ -38,14 +39,10 @@ namespace GetPlatformInfo = extensions::api::runtime::GetPlatformInfo;
 
 namespace extensions {
 
+namespace runtime = api::runtime;
+
 namespace {
 
-const char kOnStartupEvent[] = "runtime.onStartup";
-const char kOnInstalledEvent[] = "runtime.onInstalled";
-const char kOnUpdateAvailableEvent[] = "runtime.onUpdateAvailable";
-const char kOnBrowserUpdateAvailableEvent[] =
-    "runtime.onBrowserUpdateAvailable";
-const char kOnRestartRequiredEvent[] = "runtime.onRestartRequired";
 const char kNoBackgroundPageError[] = "You do not have a background page.";
 const char kPageLoadError[] = "Background page failed to load.";
 const char kInstallReason[] = "reason";
@@ -105,7 +102,8 @@ static void DispatchOnStartupEventImpl(
   }
 
   scoped_ptr<base::ListValue> event_args(new base::ListValue());
-  scoped_ptr<Event> event(new Event(kOnStartupEvent, event_args.Pass()));
+  scoped_ptr<Event> event(new Event(runtime::OnStartup::kEventName,
+                                    event_args.Pass()));
   system->event_router()->DispatchEventToExtension(extension_id, event.Pass());
 }
 
@@ -154,7 +152,8 @@ void RuntimeEventRouter::DispatchOnInstalledEvent(
     info->SetString(kInstallReason, kInstallReasonInstall);
   }
   DCHECK(system->event_router());
-  scoped_ptr<Event> event(new Event(kOnInstalledEvent, event_args.Pass()));
+  scoped_ptr<Event> event(new Event(runtime::OnInstalled::kEventName,
+                                    event_args.Pass()));
   system->event_router()->DispatchEventWithLazyListener(extension_id,
                                                         event.Pass());
 }
@@ -171,7 +170,8 @@ void RuntimeEventRouter::DispatchOnUpdateAvailableEvent(
   scoped_ptr<base::ListValue> args(new base::ListValue);
   args->Append(manifest->DeepCopy());
   DCHECK(system->event_router());
-  scoped_ptr<Event> event(new Event(kOnUpdateAvailableEvent, args.Pass()));
+  scoped_ptr<Event> event(new Event(runtime::OnUpdateAvailable::kEventName,
+                                    args.Pass()));
   system->event_router()->DispatchEventToExtension(extension_id, event.Pass());
 }
 
@@ -184,8 +184,8 @@ void RuntimeEventRouter::DispatchOnBrowserUpdateAvailableEvent(
 
   scoped_ptr<base::ListValue> args(new base::ListValue);
   DCHECK(system->event_router());
-  scoped_ptr<Event> event(new Event(kOnBrowserUpdateAvailableEvent,
-                                    args.Pass()));
+  scoped_ptr<Event> event(new Event(
+      runtime::OnBrowserUpdateAvailable::kEventName, args.Pass()));
   system->event_router()->BroadcastEvent(event.Pass());
 }
 
@@ -199,7 +199,7 @@ void RuntimeEventRouter::DispatchOnRestartRequiredEvent(
     return;
 
   scoped_ptr<Event> event(
-      new Event(kOnRestartRequiredEvent,
+      new Event(runtime::OnRestartRequired::kEventName,
                 api::runtime::OnRestartRequired::Create(reason)));
 
   DCHECK(system->event_router());
diff --git a/chrome/browser/extensions/api/storage/managed_value_store_cache.cc b/chrome/browser/extensions/api/storage/managed_value_store_cache.cc
index 4d2453a..8e98df2 100644
--- a/chrome/browser/extensions/api/storage/managed_value_store_cache.cc
+++ b/chrome/browser/extensions/api/storage/managed_value_store_cache.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/extensions/api/storage/policy_value_store.h"
 #include "chrome/browser/extensions/api/storage/settings_storage_factory.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -23,6 +22,7 @@
 #include "chrome/browser/policy/profile_policy_connector_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/value_store/value_store_change.h"
+#include "chrome/common/extensions/api/storage.h"
 #include "chrome/common/extensions/api/storage/storage_schema_manifest_handler.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_set.h"
@@ -39,6 +39,8 @@ using content::BrowserThread;
 
 namespace extensions {
 
+namespace storage = api::storage;
+
 namespace {
 
 const char kLoadSchemasBackgroundTaskTokenName[] =
@@ -180,7 +182,7 @@ ManagedValueStoreCache::ManagedValueStoreCache(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   // |event_router_| can be NULL on unit_tests.
   if (event_router_)
-    event_router_->RegisterObserver(this, event_names::kOnSettingsChanged);
+    event_router_->RegisterObserver(this, storage::OnChanged::kEventName);
 
   GetPolicyService()->AddObserver(policy::POLICY_DOMAIN_EXTENSIONS, this);
 
@@ -278,7 +280,7 @@ void ManagedValueStoreCache::UpdatePolicyOnFILE(
 void ManagedValueStoreCache::OnListenerAdded(
     const EventListenerInfo& details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK_EQ(std::string(event_names::kOnSettingsChanged), details.event_name);
+  DCHECK_EQ(std::string(storage::OnChanged::kEventName), details.event_name);
   // This is invoked on several occasions:
   //
   // 1. when an extension first registers to observe storage.onChanged; in this
diff --git a/chrome/browser/extensions/api/storage/settings_frontend.cc b/chrome/browser/extensions/api/storage/settings_frontend.cc
index 05dc82d..86f4262 100644
--- a/chrome/browser/extensions/api/storage/settings_frontend.cc
+++ b/chrome/browser/extensions/api/storage/settings_frontend.cc
@@ -29,6 +29,8 @@ using content::BrowserThread;
 
 namespace extensions {
 
+namespace storage = api::storage;
+
 namespace {
 
 // Settings change Observer which forwards changes on to the extension
@@ -49,7 +51,7 @@ class DefaultObserver : public SettingsObserver {
     args->Append(new base::StringValue(settings_namespace::ToString(
         settings_namespace)));
     scoped_ptr<Event> event(new Event(
-        event_names::kOnSettingsChanged, args.Pass()));
+        storage::OnChanged::kEventName, args.Pass()));
     ExtensionSystem::Get(profile_)->event_router()->
         DispatchEventToExtension(extension_id, event.Pass());
   }
diff --git a/chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.cc b/chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.cc
index f5a8ae7..3b93044 100644
--- a/chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.cc
+++ b/chrome/browser/extensions/api/sync_file_system/extension_sync_event_observer.cc
@@ -65,9 +65,10 @@ void ExtensionSyncEventObserver::OnSyncStateUpdated(
   scoped_ptr<base::ListValue> params(
       api::sync_file_system::OnServiceStatusChanged::Create(service_info));
 
-  BroadcastOrDispatchEvent(app_origin,
-                           event_names::kOnServiceStatusChanged,
-                           params.Pass());
+  BroadcastOrDispatchEvent(
+      app_origin,
+      api::sync_file_system::OnServiceStatusChanged::kEventName,
+      params.Pass());
 }
 
 void ExtensionSyncEventObserver::OnFileSynced(
@@ -92,9 +93,10 @@ void ExtensionSyncEventObserver::OnFileSynced(
   params->AppendString(api::sync_file_system::ToString(action_enum));
   params->AppendString(api::sync_file_system::ToString(direction_enum));
 
-  BroadcastOrDispatchEvent(url.origin(),
-                           event_names::kOnFileStatusChanged,
-                           params.Pass());
+  BroadcastOrDispatchEvent(
+      url.origin(),
+      api::sync_file_system::OnFileStatusChanged::kEventName,
+      params.Pass());
 }
 
 void ExtensionSyncEventObserver::BroadcastOrDispatchEvent(
diff --git a/chrome/browser/extensions/api/system_indicator/system_indicator_manager.cc b/chrome/browser/extensions/api/system_indicator/system_indicator_manager.cc
index a7601f0..a8b344d 100644
--- a/chrome/browser/extensions/api/system_indicator/system_indicator_manager.cc
+++ b/chrome/browser/extensions/api/system_indicator/system_indicator_manager.cc
@@ -7,7 +7,6 @@
 #include "base/memory/linked_ptr.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_action.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -24,6 +23,8 @@
 
 namespace extensions {
 
+namespace system_indicator = api::system_indicator;
+
 // Observes clicks on a given status icon and forwards the event to the
 // appropriate extension.  Handles icon updates, and responsible for creating
 // and removing the icon from the notification area during construction and
@@ -86,7 +87,7 @@ void ExtensionIndicatorIcon::OnStatusIconClicked() {
   EventRouter* event_router =
       ExtensionSystem::Get(profile_)->event_router();
   scoped_ptr<Event> event(new Event(
-      event_names::kOnSystemIndicatorClicked,
+      system_indicator::OnClicked::kEventName,
       params.Pass(),
       profile_));
   event_router->DispatchEventToExtension(
diff --git a/chrome/browser/extensions/api/system_info/system_info_api.cc b/chrome/browser/extensions/api/system_info/system_info_api.cc
index 546c878..20842a9 100644
--- a/chrome/browser/extensions/api/system_info/system_info_api.cc
+++ b/chrome/browser/extensions/api/system_info/system_info_api.cc
@@ -14,11 +14,11 @@
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/api/system_storage/storage_info_provider.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
 #include "chrome/browser/storage_monitor/removable_storage_observer.h"
 #include "chrome/browser/storage_monitor/storage_info.h"
 #include "chrome/browser/storage_monitor/storage_monitor.h"
+#include "chrome/common/extensions/api/system_display.h"
 #include "chrome/common/extensions/api/system_storage.h"
 #include "ui/gfx/display_observer.h"
 
@@ -32,10 +32,13 @@ namespace extensions {
 using api::system_storage::StorageUnitInfo;
 using content::BrowserThread;
 
+namespace system_display = api::system_display;
+namespace system_storage = api::system_storage;
+
 namespace {
 
 bool IsDisplayChangedEvent(const std::string& event_name) {
-  return event_name == event_names::kOnDisplayChanged;
+  return event_name == system_display::OnDisplayChanged::kEventName;
 }
 
 // Event router for systemInfo API. It is a singleton instance shared by
@@ -136,7 +139,7 @@ void SystemInfoEventRouter::OnRemovableStorageAttached(
   systeminfo::BuildStorageUnitInfo(info, &unit);
   scoped_ptr<base::ListValue> args(new base::ListValue);
   args->Append(unit.ToValue().release());
-  DispatchEvent(event_names::kOnStorageAttached, args.Pass());
+  DispatchEvent(system_storage::OnAttached::kEventName, args.Pass());
 }
 
 void SystemInfoEventRouter::OnRemovableStorageDetached(
@@ -145,7 +148,7 @@ void SystemInfoEventRouter::OnRemovableStorageDetached(
   args->Append(new base::StringValue(chrome::StorageMonitor::GetInstance()->
                    GetTransientIdForDeviceId(info.device_id())));
 
-  DispatchEvent(event_names::kOnStorageDetached, args.Pass());
+  DispatchEvent(system_storage::OnDetached::kEventName, args.Pass());
 }
 
 void SystemInfoEventRouter::OnDisplayBoundsChanged(
@@ -163,7 +166,7 @@ void SystemInfoEventRouter::OnDisplayRemoved(const gfx::Display& old_display) {
 
 void SystemInfoEventRouter::OnDisplayChanged() {
   scoped_ptr<base::ListValue> args(new base::ListValue());
-  DispatchEvent(event_names::kOnDisplayChanged, args.Pass());
+  DispatchEvent(system_display::OnDisplayChanged::kEventName, args.Pass());
 }
 
 void SystemInfoEventRouter::DispatchEvent(const std::string& event_name,
@@ -184,9 +187,9 @@ ProfileKeyedAPIFactory<SystemInfoAPI>* SystemInfoAPI::GetFactoryInstance() {
 
 SystemInfoAPI::SystemInfoAPI(Profile* profile) : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnStorageAttached);
+      this, system_storage::OnAttached::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnStorageDetached);
+      this, system_storage::OnDetached::kEventName);
 }
 
 SystemInfoAPI::~SystemInfoAPI() {
diff --git a/chrome/browser/extensions/api/system_private/system_private_api.cc b/chrome/browser/extensions/api/system_private/system_private_api.cc
index 758f6b7..ec42006 100644
--- a/chrome/browser/extensions/api/system_private/system_private_api.cc
+++ b/chrome/browser/extensions/api/system_private/system_private_api.cc
@@ -9,6 +9,7 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/system_private.h"
 #include "chrome/common/pref_names.h"
 
 #if defined(OS_CHROMEOS)
@@ -41,12 +42,6 @@ const char kNotAvailableState[] = "NotAvailable";
 const char kUpdatingState[] = "Updating";
 const char kNeedRestartState[] = "NeedRestart";
 
-// Event names.
-const char kOnBrightnessChanged[] = "systemPrivate.onBrightnessChanged";
-const char kOnVolumeChanged[] = "systemPrivate.onVolumeChanged";
-const char kOnScreenUnlocked[] = "systemPrivate.onScreenUnlocked";
-const char kOnWokeUp[] = "systemPrivate.onWokeUp";
-
 // Dispatches an extension event with |argument|
 void DispatchEvent(const std::string& event_name, base::Value* argument) {
   scoped_ptr<base::ListValue> list_args(new base::ListValue());
@@ -61,6 +56,8 @@ void DispatchEvent(const std::string& event_name, base::Value* argument) {
 
 namespace extensions {
 
+namespace system_private = api::system_private;
+
 bool SystemPrivateGetIncognitoModeAvailabilityFunction::RunImpl() {
   PrefService* prefs = profile_->GetPrefs();
   int value = prefs->GetInteger(prefs::kIncognitoModeAvailability);
@@ -136,22 +133,22 @@ void DispatchVolumeChangedEvent(double volume, bool is_volume_muted) {
   base::DictionaryValue* dict = new base::DictionaryValue();
   dict->SetDouble(kVolumeKey, volume);
   dict->SetBoolean(kIsVolumeMutedKey, is_volume_muted);
-  DispatchEvent(kOnVolumeChanged, dict);
+  DispatchEvent(system_private::OnVolumeChanged::kEventName, dict);
 }
 
 void DispatchBrightnessChangedEvent(int brightness, bool user_initiated) {
   base::DictionaryValue* dict = new base::DictionaryValue();
   dict->SetInteger(kBrightnessKey, brightness);
   dict->SetBoolean(kUserInitiatedKey, user_initiated);
-  DispatchEvent(kOnBrightnessChanged, dict);
+  DispatchEvent(system_private::OnBrightnessChanged::kEventName, dict);
 }
 
 void DispatchScreenUnlockedEvent() {
-  DispatchEvent(kOnScreenUnlocked, NULL);
+  DispatchEvent(system_private::OnScreenUnlocked::kEventName, NULL);
 }
 
 void DispatchWokeUpEvent() {
-  DispatchEvent(kOnWokeUp, NULL);
+  DispatchEvent(system_private::OnWokeUp::kEventName, NULL);
 }
 
 }  // namespace extensions
diff --git a/chrome/browser/extensions/api/tab_capture/tab_capture_registry.cc b/chrome/browser/extensions/api/tab_capture/tab_capture_registry.cc
index 757db57..1fa0080 100644
--- a/chrome/browser/extensions/api/tab_capture/tab_capture_registry.cc
+++ b/chrome/browser/extensions/api/tab_capture/tab_capture_registry.cc
@@ -7,7 +7,6 @@
 #include <utility>
 
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
@@ -28,6 +27,8 @@ using extensions::tab_capture::TabCaptureState;
 
 namespace extensions {
 
+namespace tab_capture = api::tab_capture;
+
 class FullscreenObserver : public content::WebContentsObserver {
  public:
   FullscreenObserver(TabCaptureRequest* request,
@@ -314,8 +315,8 @@ void TabCaptureRegistry::DispatchStatusChangeEvent(
 
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(info->ToValue().release());
-  scoped_ptr<Event> event(new Event(
-      extensions::event_names::kOnTabCaptureStatusChanged, args.Pass()));
+  scoped_ptr<Event> event(new Event(tab_capture::OnStatusChanged::kEventName,
+      args.Pass()));
   event->restrict_to_profile = profile_;
 
   router->DispatchEventToExtension(request->extension_id, event.Pass());
diff --git a/chrome/browser/extensions/api/tabs/tabs_windows_api.cc b/chrome/browser/extensions/api/tabs/tabs_windows_api.cc
index 24cb81d..5f40de2 100644
--- a/chrome/browser/extensions/api/tabs/tabs_windows_api.cc
+++ b/chrome/browser/extensions/api/tabs/tabs_windows_api.cc
@@ -6,20 +6,22 @@
 
 #include "base/lazy_instance.h"
 #include "chrome/browser/extensions/api/tabs/windows_event_router.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
+#include "chrome/common/extensions/api/windows.h"
 
 namespace extensions {
 
+namespace windows = api::windows;
+
 TabsWindowsAPI::TabsWindowsAPI(Profile* profile)
     : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnWindowCreated);
+      this, windows::OnCreated::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnWindowRemoved);
+      this, windows::OnRemoved::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, event_names::kOnWindowFocusedChanged);
+      this, windows::OnFocusChanged::kEventName);
 }
 
 TabsWindowsAPI::~TabsWindowsAPI() {
diff --git a/chrome/browser/extensions/api/tabs/windows_event_router.cc b/chrome/browser/extensions/api/tabs/windows_event_router.cc
index e6a8a57..efdac24 100644
--- a/chrome/browser/extensions/api/tabs/windows_event_router.cc
+++ b/chrome/browser/extensions/api/tabs/windows_event_router.cc
@@ -6,13 +6,13 @@
 
 #include "base/values.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/window_controller.h"
 #include "chrome/browser/extensions/window_controller_list.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/windows.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "content/public/browser/notification_service.h"
 
@@ -20,10 +20,10 @@
 #include "ui/base/x/active_window_watcher_x.h"
 #endif
 
-namespace event_names = extensions::event_names;
-
 namespace extensions {
 
+namespace windows = extensions::api::windows;
+
 WindowsEventRouter::WindowsEventRouter(Profile* profile)
     : profile_(profile),
       focused_profile_(NULL),
@@ -61,7 +61,7 @@ void WindowsEventRouter::OnWindowControllerAdded(
   base::DictionaryValue* window_dictionary =
       window_controller->CreateWindowValue();
   args->Append(window_dictionary);
-  DispatchEvent(event_names::kOnWindowCreated, window_controller->profile(),
+  DispatchEvent(windows::OnCreated::kEventName, window_controller->profile(),
                 args.Pass());
 }
 
@@ -73,7 +73,8 @@ void WindowsEventRouter::OnWindowControllerRemoved(
   int window_id = window_controller->GetWindowId();
   scoped_ptr<base::ListValue> args(new base::ListValue());
   args->Append(new base::FundamentalValue(window_id));
-  DispatchEvent(event_names::kOnWindowRemoved, window_controller->profile(),
+  DispatchEvent(windows::OnRemoved::kEventName,
+                window_controller->profile(),
                 args.Pass());
 }
 
@@ -143,7 +144,7 @@ void WindowsEventRouter::OnActiveWindowChanged(
   focused_profile_ = window_profile;
   focused_window_id_ = window_id;
 
-  scoped_ptr<Event> event(new Event(event_names::kOnWindowFocusedChanged,
+  scoped_ptr<Event> event(new Event(windows::OnFocusChanged::kEventName,
                                     make_scoped_ptr(new base::ListValue())));
   event->will_dispatch_callback =
       base::Bind(&WillDispatchWindowFocusedEvent, window_profile, window_id);
diff --git a/chrome/browser/extensions/api/terminal/terminal_private_api.cc b/chrome/browser/extensions/api/terminal/terminal_private_api.cc
index fb5ef8a..a7cfdcb 100644
--- a/chrome/browser/extensions/api/terminal/terminal_private_api.cc
+++ b/chrome/browser/extensions/api/terminal/terminal_private_api.cc
@@ -9,7 +9,6 @@
 #include "base/json/json_writer.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/api/terminal/terminal_extension_helper.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -18,6 +17,7 @@
 #include "chromeos/process_proxy/process_proxy_registry.h"
 #include "content/public/browser/browser_thread.h"
 
+namespace terminal_private = extensions::api::terminal_private;
 namespace OnTerminalResize =
     extensions::api::terminal_private::OnTerminalResize;
 namespace OpenTerminalProcess =
@@ -65,7 +65,7 @@ void NotifyProcessOutput(Profile* profile,
   if (profile &&
       extensions::ExtensionSystem::Get(profile)->event_router()) {
     scoped_ptr<extensions::Event> event(new extensions::Event(
-        extensions::event_names::kOnTerminalProcessOutput, args.Pass()));
+        terminal_private::OnProcessOutput::kEventName, args.Pass()));
     extensions::ExtensionSystem::Get(profile)->event_router()->
         DispatchEventToExtension(extension_id, event.Pass());
   }
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
index 73c80f1..7e2c8db 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
@@ -41,6 +41,7 @@ namespace extensions {
 
 namespace helpers = web_navigation_api_helpers;
 namespace keys = web_navigation_api_constants;
+namespace web_navigation = api::web_navigation;
 
 namespace {
 
@@ -453,7 +454,7 @@ void WebNavigationTabObserver::DidCommitProvisionalLoadForFrame(
 
   if (is_reference_fragment_navigation) {
     helpers::DispatchOnCommitted(
-        keys::kOnReferenceFragmentUpdated,
+        web_navigation::OnReferenceFragmentUpdated::kEventName,
         web_contents(),
         frame_num,
         is_main_frame,
@@ -461,7 +462,7 @@ void WebNavigationTabObserver::DidCommitProvisionalLoadForFrame(
         transition_type);
   } else if (is_history_state_modification) {
     helpers::DispatchOnCommitted(
-        keys::kOnHistoryStateUpdated,
+        web_navigation::OnHistoryStateUpdated::kEventName,
         web_contents(),
         frame_num,
         is_main_frame,
@@ -473,7 +474,7 @@ void WebNavigationTabObserver::DidCommitProvisionalLoadForFrame(
           transition_type | content::PAGE_TRANSITION_SERVER_REDIRECT);
     }
     helpers::DispatchOnCommitted(
-        keys::kOnCommitted,
+        web_navigation::OnCommitted::kEventName,
         web_contents(),
         frame_num,
         is_main_frame,
@@ -820,23 +821,23 @@ bool WebNavigationGetAllFramesFunction::RunImpl() {
 WebNavigationAPI::WebNavigationAPI(Profile* profile)
     : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnBeforeNavigate);
+      this, web_navigation::OnBeforeNavigate::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnCommitted);
+      this, web_navigation::OnCommitted::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnCompleted);
+      this, web_navigation::OnCompleted::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnCreatedNavigationTarget);
+      this, web_navigation::OnCreatedNavigationTarget::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnDOMContentLoaded);
+      this, web_navigation::OnDOMContentLoaded::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnHistoryStateUpdated);
+      this, web_navigation::OnHistoryStateUpdated::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnErrorOccurred);
+      this, web_navigation::OnErrorOccurred::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnReferenceFragmentUpdated);
+      this, web_navigation::OnReferenceFragmentUpdated::kEventName);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
-      this, keys::kOnTabReplaced);
+      this, web_navigation::OnTabReplaced::kEventName);
 }
 
 WebNavigationAPI::~WebNavigationAPI() {
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api_constants.cc b/chrome/browser/extensions/api/web_navigation/web_navigation_api_constants.cc
index be8ac77..785cbfa 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api_constants.cc
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api_constants.cc
@@ -22,19 +22,6 @@ const char kTransitionTypeKey[] = "transitionType";
 const char kTransitionQualifiersKey[] = "transitionQualifiers";
 const char kUrlKey[] = "url";
 
-const char kOnBeforeNavigate[] = "webNavigation.onBeforeNavigate";
-const char kOnCommitted[] = "webNavigation.onCommitted";
-const char kOnCompleted[] = "webNavigation.onCompleted";
-const char kOnCreatedNavigationTarget[] =
-    "webNavigation.onCreatedNavigationTarget";
-const char kOnDOMContentLoaded[] =
-    "webNavigation.onDOMContentLoaded";
-const char kOnHistoryStateUpdated[] = "webNavigation.onHistoryStateUpdated";
-const char kOnErrorOccurred[] = "webNavigation.onErrorOccurred";
-const char kOnReferenceFragmentUpdated[] =
-    "webNavigation.onReferenceFragmentUpdated";
-const char kOnTabReplaced[] = "webNavigation.onTabReplaced";
-
 }  // namespace web_navigation_api_constants
 
 }  // namespace extensions
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.cc b/chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.cc
index b684650..4648b5f 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.cc
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.cc
@@ -15,6 +15,7 @@
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/web_navigation.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
@@ -24,6 +25,7 @@
 namespace extensions {
 
 namespace keys = web_navigation_api_constants;
+namespace web_navigation = api::web_navigation;
 
 namespace web_navigation_api_helpers {
 
@@ -77,7 +79,7 @@ void DispatchOnBeforeNavigate(content::WebContents* web_contents,
   args->Append(dict);
 
   DispatchEvent(web_contents->GetBrowserContext(),
-                keys::kOnBeforeNavigate,
+                web_navigation::OnBeforeNavigate::kEventName,
                 args.Pass(),
                 validated_url);
 }
@@ -134,7 +136,7 @@ void DispatchOnDOMContentLoaded(content::WebContents* web_contents,
   args->Append(dict);
 
   DispatchEvent(web_contents->GetBrowserContext(),
-                keys::kOnDOMContentLoaded,
+                web_navigation::OnDOMContentLoaded::kEventName,
                 args.Pass(),
                 url);
 }
@@ -155,7 +157,8 @@ void DispatchOnCompleted(content::WebContents* web_contents,
   dict->SetDouble(keys::kTimeStampKey, MilliSecondsFromTime(base::Time::Now()));
   args->Append(dict);
 
-  DispatchEvent(web_contents->GetBrowserContext(), keys::kOnCompleted,
+  DispatchEvent(web_contents->GetBrowserContext(),
+                web_navigation::OnCompleted::kEventName,
                 args.Pass(), url);
 }
 
@@ -188,7 +191,9 @@ void DispatchOnCreatedNavigationTarget(
   dict->SetDouble(keys::kTimeStampKey, MilliSecondsFromTime(base::Time::Now()));
   args->Append(dict);
 
-  DispatchEvent(browser_context, keys::kOnCreatedNavigationTarget, args.Pass(),
+  DispatchEvent(browser_context,
+                web_navigation::OnCreatedNavigationTarget::kEventName,
+                args.Pass(),
                 target_url);
 }
 
@@ -206,10 +211,12 @@ void DispatchOnErrorOccurred(content::WebContents* web_contents,
   dict->SetInteger(keys::kProcessIdKey, render_process_id);
   dict->SetInteger(keys::kFrameIdKey, GetFrameId(is_main_frame, frame_id));
   dict->SetString(keys::kErrorKey, net::ErrorToString(error_code));
-  dict->SetDouble(keys::kTimeStampKey, MilliSecondsFromTime(base::Time::Now()));
+  dict->SetDouble(keys::kTimeStampKey,
+      MilliSecondsFromTime(base::Time::Now()));
   args->Append(dict);
 
-  DispatchEvent(web_contents->GetBrowserContext(), keys::kOnErrorOccurred,
+  DispatchEvent(web_contents->GetBrowserContext(),
+                web_navigation::OnErrorOccurred::kEventName,
                 args.Pass(), url);
 }
 
@@ -222,12 +229,16 @@ void DispatchOnTabReplaced(
   base::DictionaryValue* dict = new base::DictionaryValue();
   dict->SetInteger(keys::kReplacedTabIdKey,
                    ExtensionTabUtil::GetTabId(old_web_contents));
-  dict->SetInteger(keys::kTabIdKey,
-                   ExtensionTabUtil::GetTabId(new_web_contents));
+  dict->SetInteger(
+      keys::kTabIdKey,
+      ExtensionTabUtil::GetTabId(new_web_contents));
   dict->SetDouble(keys::kTimeStampKey, MilliSecondsFromTime(base::Time::Now()));
   args->Append(dict);
 
-  DispatchEvent(browser_context, keys::kOnTabReplaced, args.Pass(), GURL());
+  DispatchEvent(browser_context,
+                web_navigation::OnTabReplaced::kEventName,
+                args.Pass(),
+                GURL());
 }
 
 }  // namespace web_navigation_api_helpers
diff --git a/chrome/browser/extensions/api/web_request/web_request_api.cc b/chrome/browser/extensions/api/web_request/web_request_api.cc
index 478c990..acccfcf 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api.cc
@@ -93,10 +93,10 @@ const char kWebView[] = "webview";
 // List of all the webRequest events.
 const char* const kWebRequestEvents[] = {
   keys::kOnBeforeRedirectEvent,
-  keys::kOnBeforeRequestEvent,
+  web_request::OnBeforeRequest::kEventName,
   keys::kOnBeforeSendHeadersEvent,
   keys::kOnCompletedEvent,
-  keys::kOnErrorOccurredEvent,
+  web_request::OnErrorOccurred::kEventName,
   keys::kOnSendHeadersEvent,
   keys::kOnAuthRequiredEvent,
   keys::kOnResponseStartedEvent,
@@ -631,13 +631,13 @@ int ExtensionWebRequestEventRouter::OnBeforeRequest(
 
   initialize_blocked_requests |=
       ProcessDeclarativeRules(profile, extension_info_map,
-                              keys::kOnBeforeRequestEvent, request,
+                              web_request::OnBeforeRequest::kEventName, request,
                               extensions::ON_BEFORE_REQUEST, NULL);
 
   int extra_info_spec = 0;
   std::vector<const EventListener*> listeners =
       GetMatchingListeners(profile, extension_info_map,
-                           keys::kOnBeforeRequestEvent, request,
+                           web_request::OnBeforeRequest::kEventName, request,
                            &extra_info_spec);
   if (!listeners.empty() &&
       !GetAndSetSignaled(request->identifier(), kOnBeforeRequest)) {
@@ -1057,7 +1057,7 @@ void ExtensionWebRequestEventRouter::OnErrorOccurred(
   int extra_info_spec = 0;
   std::vector<const EventListener*> listeners =
       GetMatchingListeners(profile, extension_info_map,
-                           keys::kOnErrorOccurredEvent, request,
+                           web_request::OnErrorOccurred::kEventName, request,
                            &extra_info_spec);
   if (listeners.empty())
     return;
diff --git a/chrome/browser/extensions/api/web_request/web_request_api_constants.cc b/chrome/browser/extensions/api/web_request/web_request_api_constants.cc
index ffcd8dd..493a903d 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api_constants.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api_constants.cc
@@ -44,10 +44,8 @@ const char kUsernameKey[] = "username";
 const char kPasswordKey[] = "password";
 
 const char kOnBeforeRedirectEvent[] = "webRequest.onBeforeRedirect";
-const char kOnBeforeRequestEvent[] = "webRequest.onBeforeRequest";
 const char kOnBeforeSendHeadersEvent[] = "webRequest.onBeforeSendHeaders";
 const char kOnCompletedEvent[] = "webRequest.onCompleted";
-const char kOnErrorOccurredEvent[] = "webRequest.onErrorOccurred";
 const char kOnHeadersReceivedEvent[] = "webRequest.onHeadersReceived";
 const char kOnResponseStartedEvent[] = "webRequest.onResponseStarted";
 const char kOnSendHeadersEvent[] = "webRequest.onSendHeaders";
diff --git a/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc b/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
index 1a71294..ac8fb70 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
@@ -29,6 +29,7 @@
 #include "chrome/browser/extensions/extension_warning_set.h"
 #include "chrome/browser/net/about_protocol_handler.h"
 #include "chrome/browser/net/chrome_network_delegate.h"
+#include "chrome/common/extensions/api/web_request.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "chrome/common/extensions/features/feature.h"
 #include "chrome/common/pref_names.h"
@@ -52,6 +53,7 @@
 
 namespace helpers = extension_web_request_api_helpers;
 namespace keys = extension_web_request_api_constants;
+namespace web_request = extensions::api::web_request;
 
 using base::BinaryValue;
 using base::DictionaryValue;
@@ -218,7 +220,7 @@ TEST_F(ExtensionWebRequestTest, BlockingEventPrecedenceRedirect) {
   std::string extension1_id("1");
   std::string extension2_id("2");
   ExtensionWebRequestEventRouter::RequestFilter filter;
-  const std::string kEventName(keys::kOnBeforeRequestEvent);
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
   base::WeakPtrFactory<TestIPCSender> ipc_sender_factory(&ipc_sender_);
   ExtensionWebRequestEventRouter::GetInstance()->AddEventListener(
       &profile_, extension1_id, extension1_id, kEventName, kEventName + "/1",
@@ -353,7 +355,7 @@ TEST_F(ExtensionWebRequestTest, BlockingEventPrecedenceCancel) {
   std::string extension1_id("1");
   std::string extension2_id("2");
   ExtensionWebRequestEventRouter::RequestFilter filter;
-  const std::string kEventName(keys::kOnBeforeRequestEvent);
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
   base::WeakPtrFactory<TestIPCSender> ipc_sender_factory(&ipc_sender_);
   ExtensionWebRequestEventRouter::GetInstance()->AddEventListener(
     &profile_, extension1_id, extension1_id, kEventName, kEventName + "/1",
@@ -420,8 +422,8 @@ TEST_F(ExtensionWebRequestTest, SimulateChancelWhileBlocked) {
   ExtensionWebRequestEventRouter::RequestFilter filter;
 
   // Subscribe to OnBeforeRequest and OnErrorOccurred.
-  const std::string kEventName(keys::kOnBeforeRequestEvent);
-  const std::string kEventName2(keys::kOnErrorOccurredEvent);
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
+  const std::string kEventName2(web_request::OnErrorOccurred::kEventName);
   base::WeakPtrFactory<TestIPCSender> ipc_sender_factory(&ipc_sender_);
   ExtensionWebRequestEventRouter::GetInstance()->AddEventListener(
     &profile_, extension_id, extension_id, kEventName, kEventName + "/1",
@@ -604,7 +606,7 @@ TEST_F(ExtensionWebRequestTest, AccessRequestBodyData) {
 #undef kBoundary
 
   // Set up a dummy extension name.
-  const std::string kEventName(keys::kOnBeforeRequestEvent);
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
   ExtensionWebRequestEventRouter::RequestFilter filter;
   std::string extension_id("1");
   const std::string string_spec_post("blocking,requestBody");
@@ -695,7 +697,7 @@ TEST_F(ExtensionWebRequestTest, NoAccessRequestBodyData) {
   const char* kMethods[] = { "POST", "PUT", "GET" };
 
   // Set up a dummy extension name.
-  const std::string kEventName(keys::kOnBeforeRequestEvent);
+  const std::string kEventName(web_request::OnBeforeRequest::kEventName);
   ExtensionWebRequestEventRouter::RequestFilter filter;
   const std::string extension_id("1");
   int extra_info_spec = 0;
diff --git a/chrome/browser/extensions/browser_event_router.cc b/chrome/browser/extensions/browser_event_router.cc
index 635781a..baa4171 100644
--- a/chrome/browser/extensions/browser_event_router.cc
+++ b/chrome/browser/extensions/browser_event_router.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/extensions/api/tabs/tabs_constants.h"
 #include "chrome/browser/extensions/api/tabs/tabs_windows_api.h"
 #include "chrome/browser/extensions/api/tabs/windows_event_router.h"
-#include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/extension_action.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ -31,7 +30,6 @@
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/web_contents.h"
 
-namespace events = extensions::event_names;
 namespace tab_keys = extensions::tabs_constants;
 namespace page_actions_keys = extension_page_actions_api_constants;
 
@@ -40,6 +38,8 @@ using content::WebContents;
 
 namespace extensions {
 
+namespace tabs = api::tabs;
+
 BrowserEventRouter::TabEntry::TabEntry()
     : complete_waiting_on_load_(false),
       url_() {
@@ -178,7 +178,7 @@ void BrowserEventRouter::TabCreatedAt(WebContents* contents,
                                       bool active) {
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
   scoped_ptr<base::ListValue> args(new base::ListValue());
-  scoped_ptr<Event> event(new Event(events::kOnTabCreated, args.Pass()));
+  scoped_ptr<Event> event(new Event(tabs::OnCreated::kEventName, args.Pass()));
   event->restrict_to_profile = profile;
   event->user_gesture = EventRouter::USER_GESTURE_NOT_ENABLED;
   event->will_dispatch_callback =
@@ -211,7 +211,7 @@ void BrowserEventRouter::TabInsertedAt(WebContents* contents,
   args->Append(object_args);
 
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabAttached, args.Pass(),
+  DispatchEvent(profile, tabs::OnAttached::kEventName, args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 }
 
@@ -233,7 +233,7 @@ void BrowserEventRouter::TabDetachedAt(WebContents* contents, int index) {
   args->Append(object_args);
 
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabDetached, args.Pass(),
+  DispatchEvent(profile, tabs::OnDetached::kEventName, args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 }
 
@@ -253,7 +253,7 @@ void BrowserEventRouter::TabClosingAt(TabStripModel* tab_strip_model,
   args->Append(object_args);
 
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabRemoved, args.Pass(),
+  DispatchEvent(profile, tabs::OnRemoved::kEventName, args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 
   int removed_count = tab_entries_.erase(tab_id);
@@ -283,15 +283,15 @@ void BrowserEventRouter::ActiveTabChanged(WebContents* old_contents,
       reason & CHANGE_REASON_USER_GESTURE
       ? EventRouter::USER_GESTURE_ENABLED
       : EventRouter::USER_GESTURE_NOT_ENABLED;
-  DispatchEvent(profile, events::kOnTabSelectionChanged,
+  DispatchEvent(profile, tabs::OnSelectionChanged::kEventName,
                 scoped_ptr<base::ListValue>(args->DeepCopy()), gesture);
-  DispatchEvent(profile, events::kOnTabActiveChanged,
+  DispatchEvent(profile, tabs::OnActiveChanged::kEventName,
                 scoped_ptr<base::ListValue>(args->DeepCopy()), gesture);
 
   // The onActivated event takes one argument: {windowId, tabId}.
   args->Remove(0, NULL);
   object_args->Set(tab_keys::kTabIdKey, new base::FundamentalValue(tab_id));
-  DispatchEvent(profile, events::kOnTabActivated, args.Pass(), gesture);
+  DispatchEvent(profile, tabs::OnActivated::kEventName, args.Pass(), gesture);
 }
 
 void BrowserEventRouter::TabSelectionChanged(
@@ -321,10 +321,10 @@ void BrowserEventRouter::TabSelectionChanged(
 
   // The onHighlighted event replaced onHighlightChanged.
   Profile* profile = tab_strip_model->profile();
-  DispatchEvent(profile, events::kOnTabHighlightChanged,
+  DispatchEvent(profile, tabs::OnHighlightChanged::kEventName,
                 scoped_ptr<base::ListValue>(args->DeepCopy()),
                 EventRouter::USER_GESTURE_UNKNOWN);
-  DispatchEvent(profile, events::kOnTabHighlighted, args.Pass(),
+  DispatchEvent(profile, tabs::OnHighlighted::kEventName, args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 }
 
@@ -345,7 +345,7 @@ void BrowserEventRouter::TabMoved(WebContents* contents,
   args->Append(object_args);
 
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabMoved, args.Pass(),
+  DispatchEvent(profile, tabs::OnMoved::kEventName, args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 }
 
@@ -462,7 +462,8 @@ void BrowserEventRouter::DispatchTabUpdatedEvent(
   // WillDispatchTabUpdatedEvent.
   Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
 
-  scoped_ptr<Event> event(new Event(events::kOnTabUpdated, args_base.Pass()));
+  scoped_ptr<Event> event(new Event(tabs::OnUpdated::kEventName,
+      args_base.Pass()));
   event->restrict_to_profile = profile;
   event->user_gesture = EventRouter::USER_GESTURE_NOT_ENABLED;
   event->will_dispatch_callback =
@@ -524,7 +525,7 @@ void BrowserEventRouter::TabReplacedAt(TabStripModel* tab_strip_model,
   args->Append(new base::FundamentalValue(old_tab_id));
 
   DispatchEvent(Profile::FromBrowserContext(new_contents->GetBrowserContext()),
-                events::kOnTabReplaced,
+                tabs::OnReplaced::kEventName,
                 args.Pass(),
                 EventRouter::USER_GESTURE_UNKNOWN);
 
diff --git a/chrome/browser/extensions/event_names.cc b/chrome/browser/extensions/event_names.cc
index 2fb55be..5c59a39 100644
--- a/chrome/browser/extensions/event_names.cc
+++ b/chrome/browser/extensions/event_names.cc
@@ -8,28 +8,6 @@ namespace extensions {
 
 namespace event_names {
 
-const char kOnTabActivated[] = "tabs.onActivated";
-const char kOnTabActiveChanged[] = "tabs.onActiveChanged";
-const char kOnTabAttached[] = "tabs.onAttached";
-const char kOnTabCreated[] = "tabs.onCreated";
-const char kOnTabDetached[] = "tabs.onDetached";
-const char kOnTabHighlightChanged[] = "tabs.onHighlightChanged";
-const char kOnTabHighlighted[] = "tabs.onHighlighted";
-const char kOnTabMoved[] = "tabs.onMoved";
-const char kOnTabRemoved[] = "tabs.onRemoved";
-const char kOnTabReplaced[] = "tabs.onReplaced";
-const char kOnTabSelectionChanged[] = "tabs.onSelectionChanged";
-const char kOnTabUpdated[] = "tabs.onUpdated";
-
-const char kOnWindowCreated[] = "windows.onCreated";
-const char kOnWindowFocusedChanged[] = "windows.onFocusChanged";
-const char kOnWindowRemoved[] = "windows.onRemoved";
-
-const char kOnExtensionInstalled[] = "management.onInstalled";
-const char kOnExtensionUninstalled[] = "management.onUninstalled";
-const char kOnExtensionEnabled[] = "management.onEnabled";
-const char kOnExtensionDisabled[] = "management.onDisabled";
-
 const char kOnDirectoryChanged[] = "fileBrowserPrivate.onDirectoryChanged";
 const char kOnFileBrowserMountCompleted[] =
     "fileBrowserPrivate.onMountCompleted";
@@ -43,72 +21,20 @@ const char kOnFileBrowserDriveConnectionStatusChanged[] =
 const char kOnInputMethodChanged[] = "inputMethodPrivate.onChanged";
 
 const char kOnContextMenus[] = "contextMenus";
-const char kOnContextMenuClicked[] = "contextMenus.onClicked";
-
-const char kOnDialDeviceList[] = "dial.onDeviceList";
-const char kOnDialError[] = "dial.onError";
-
-const char kOnDownloadCreated[] = "downloads.onCreated";
-const char kOnDownloadChanged[] = "downloads.onChanged";
-const char kOnDownloadErased[] = "downloads.onErased";
-const char kOnDownloadDeterminingFilename[] = "downloads.onDeterminingFilename";
-
-const char kOnSettingsChanged[] = "storage.onChanged";
-
-const char kOnTerminalProcessOutput[] = "terminalPrivate.onProcessOutput";
 
 const char kOnOffscreenTabUpdated[] = "experimental.offscreenTabs.onUpdated";
 
-const char kOnTabCaptureStatusChanged[] = "tabCapture.onStatusChanged";
-
-const char kBluetoothOnAdapterStateChanged[] =
-    "bluetooth.onAdapterStateChanged";
-const char kBluetoothOnConnection[] = "bluetooth.onConnection";
 const char kBluetoothOnDeviceDiscovered[] = "bluetooth.onDeviceDiscovered";
 const char kBluetoothOnDeviceSearchFinished[] =
     "bluetooth.onDeviceSearchFinished";
 const char kBluetoothOnDeviceSearchResult[] = "bluetooth.onDeviceSearchResult";
 
-const char kOnPushMessage[] = "pushMessaging.onMessage";
-
 const char kOnDisplayChanged[] = "system.display.onDisplayChanged";
 const char kOnStorageAvailableCapacityChanged[] =
     "system.storage.onAvailableCapacityChanged";
-const char kOnStorageAttached[] = "system.storage.onAttached";
-const char kOnStorageDetached[] = "system.storage.onDetached";
-
-const char kOnSystemIndicatorClicked[] = "systemIndicator.onClicked";
-
-const char kOnServiceStatusChanged[] = "syncFileSystem.onServiceStatusChanged";
-const char kOnFileStatusChanged[] = "syncFileSystem.onFileStatusChanged";
-
-const char kOnAttachEventName[] = "mediaGalleriesPrivate.onDeviceAttached";
-const char kOnDetachEventName[] = "mediaGalleriesPrivate.onDeviceDetached";
-const char kOnGalleryChangedEventName[] =
-    "mediaGalleriesPrivate.onGalleryChanged";
 
 const char kOnNotificationDisplayed[] = "notifications.onDisplayed";
 const char kOnNotificationError[] = "notifications.onError";
-const char kOnNotificationClosed[] = "notifications.onClosed";
-const char kOnNotificationClicked[] = "notifications.onClicked";
-const char kOnNotificationButtonClicked[] = "notifications.onButtonClicked";
-
-const char kOnNetworksChanged[] = "networkingPrivate.onNetworksChanged";
-const char kOnNetworkListChanged[] = "networkingPrivate.onNetworkListChanged";
-
-const char kOnAudioDeviceChanged[] = "audio.onDeviceChanged";
-
-const char kOnLaunched[] = "app.runtime.onLaunched";
-const char kOnRestarted[] = "app.runtime.onRestarted";
-
-const char kOnFeedbackRequested[] = "feedbackPrivate.onFeedbackRequested";
-
-const char kDeveloperPrivateOnItemStateChanged[] =
-    "developerPrivate.onItemStateChanged";
-
-const char kRecoveryOnWriteProgress[] = "recoveryPrivate.onWriteProgress";
-const char kRecoveryOnWriteComplete[] = "recoveryPrivate.onWriteComplete";
-const char kRecoveryOnWriteError[] = "recoveryPrivate.onWriteError";
 
 }  // namespace event_names
 
diff --git a/chrome/browser/extensions/event_names.h b/chrome/browser/extensions/event_names.h
index 9e005e2..0a1ebd6d 100644
--- a/chrome/browser/extensions/event_names.h
+++ b/chrome/browser/extensions/event_names.h
@@ -11,31 +11,6 @@ namespace extensions {
 
 namespace event_names {
 
-// Tabs.
-extern const char kOnTabActivated[];
-extern const char kOnTabActiveChanged[];
-extern const char kOnTabAttached[];
-extern const char kOnTabCreated[];
-extern const char kOnTabDetached[];
-extern const char kOnTabHighlightChanged[];
-extern const char kOnTabHighlighted[];
-extern const char kOnTabMoved[];
-extern const char kOnTabRemoved[];
-extern const char kOnTabReplaced[];
-extern const char kOnTabSelectionChanged[];
-extern const char kOnTabUpdated[];
-
-// Windows.
-extern const char kOnWindowCreated[];
-extern const char kOnWindowFocusedChanged[];
-extern const char kOnWindowRemoved[];
-
-// Management.
-extern const char kOnExtensionInstalled[];
-extern const char kOnExtensionUninstalled[];
-extern const char kOnExtensionEnabled[];
-extern const char kOnExtensionDisabled[];
-
 // FileBrowser.
 extern const char kOnDirectoryChanged[];
 extern const char kOnFileBrowserMountCompleted[];
@@ -49,86 +24,22 @@ extern const char kOnInputMethodChanged[];
 
 // Context menus.
 extern const char kOnContextMenus[];
-extern const char kOnContextMenuClicked[];
-
-// DIAL.
-extern const char kOnDialDeviceList[];
-extern const char kOnDialError[];
-
-// Downloads.
-extern const char kOnDownloadCreated[];
-extern const char kOnDownloadChanged[];
-extern const char kOnDownloadErased[];
-extern const char kOnDownloadDeterminingFilename[];
-
-// Settings.
-extern const char kOnSettingsChanged[];
-
-// TerminalPrivate.
-extern const char kOnTerminalProcessOutput[];
 
 // OffscreenTabs.
 extern const char kOnOffscreenTabUpdated[];
 
-// Tab content capture.
-extern const char kOnTabCaptureStatusChanged[];
-
 // Bluetooth.
-extern const char kBluetoothOnAdapterStateChanged[];
-extern const char kBluetoothOnConnection[];
 extern const char kBluetoothOnDeviceDiscovered[];
 extern const char kBluetoothOnDeviceSearchFinished[];
 extern const char kBluetoothOnDeviceSearchResult[];
 
-// Push messaging.
-extern const char kOnPushMessage[];
-
 // systemInfo event names.
 extern const char kOnDisplayChanged[];
 extern const char kOnStorageAvailableCapacityChanged[];
-extern const char kOnStorageAttached[];
-extern const char kOnStorageDetached[];
-
-// System Indicator icon.
-extern const char kOnSystemIndicatorClicked[];
-
-// SyncFileSystem.
-extern const char kOnServiceStatusChanged[];
-extern const char kOnFileStatusChanged[];
-
-// MediaGalleriesPrivate.
-extern const char kOnAttachEventName[];
-extern const char kOnDetachEventName[];
-extern const char kOnGalleryChangedEventName[];
 
 // Notifications.
 extern const char kOnNotificationDisplayed[];
 extern const char kOnNotificationError[];
-extern const char kOnNotificationClosed[];
-extern const char kOnNotificationClicked[];
-extern const char kOnNotificationButtonClicked[];
-
-// NetworkingPrivate
-extern const char kOnNetworksChanged[];
-extern const char kOnNetworkListChanged[];
-
-// Audio
-extern const char kOnAudioDeviceChanged[];
-
-// Runtime.
-extern const char kOnLaunched[];
-extern const char kOnRestarted[];
-
-// FeedbackPrivate
-extern const char kOnFeedbackRequested[];
-
-// DeveloperPrivate.
-extern const char kDeveloperPrivateOnItemStateChanged[];
-
-// ImageWriter
-extern const char kRecoveryOnWriteProgress[];
-extern const char kRecoveryOnWriteComplete[];
-extern const char kRecoveryOnWriteError[];
 
 }  // namespace event_names
 
diff --git a/chrome/browser/extensions/menu_manager.cc b/chrome/browser/extensions/menu_manager.cc
index 2091db8..6b0303d 100644
--- a/chrome/browser/extensions/menu_manager.cc
+++ b/chrome/browser/extensions/menu_manager.cc
@@ -21,6 +21,7 @@
 #include "chrome/browser/extensions/state_store.h"
 #include "chrome/browser/extensions/tab_helper.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/common/extensions/api/context_menus.h"
 #include "chrome/common/extensions/background_info.h"
 #include "chrome/common/extensions/extension.h"
 #include "content/public/browser/notification_details.h"
@@ -35,6 +36,8 @@ using extensions::ExtensionSystem;
 
 namespace extensions {
 
+namespace context_menus = api::context_menus;
+
 namespace {
 
 // Keys for serialization to and from Value to store in the preferences.
@@ -681,7 +684,7 @@ void MenuManager::ExecuteCommand(Profile* profile,
     event_router->DispatchEventToExtension(item->extension_id(), event.Pass());
   }
   {
-    scoped_ptr<Event> event(new Event(event_names::kOnContextMenuClicked,
+    scoped_ptr<Event> event(new Event(context_menus::OnClicked::kEventName,
                                       args.Pass()));
     event->restrict_to_profile = profile;
     event->user_gesture = EventRouter::USER_GESTURE_ENABLED;
diff --git a/chrome/browser/extensions/menu_manager_unittest.cc b/chrome/browser/extensions/menu_manager_unittest.cc
index 5b402be..80e7c60 100644
--- a/chrome/browser/extensions/menu_manager_unittest.cc
+++ b/chrome/browser/extensions/menu_manager_unittest.cc
@@ -21,6 +21,7 @@
 #include "chrome/browser/extensions/test_extension_system.h"
 #include "chrome/browser/prefs/pref_service_syncable.h"
 #include "chrome/common/chrome_paths.h"
+#include "chrome/common/extensions/api/context_menus.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/test/base/testing_profile.h"
@@ -40,6 +41,8 @@ using testing::SaveArg;
 
 namespace extensions {
 
+namespace context_menus = api::context_menus;
+
 // Base class for tests.
 class MenuManagerTest : public testing::Test {
  public:
@@ -588,7 +591,7 @@ TEST_F(MenuManagerTest, ExecuteCommand) {
     EXPECT_CALL(*mock_event_router,
               DispatchEventToExtensionMock(
                   item->extension_id(),
-                  extensions::event_names::kOnContextMenuClicked,
+                  context_menus::OnClicked::kEventName,
                   _,
                   &profile,
                   GURL(),
diff --git a/chrome/browser/extensions/permissions_updater.cc b/chrome/browser/extensions/permissions_updater.cc
index e52af60..5ca9f53 100644
--- a/chrome/browser/extensions/permissions_updater.cc
+++ b/chrome/browser/extensions/permissions_updater.cc
@@ -27,12 +27,7 @@ using extensions::permissions_api_helpers::PackPermissionSet;
 
 namespace extensions {
 
-namespace {
-
-const char kOnAdded[] = "permissions.onAdded";
-const char kOnRemoved[] = "permissions.onRemoved";
-
-}  // namespace
+namespace permissions = api::permissions;
 
 PermissionsUpdater::PermissionsUpdater(Profile* profile)
     : profile_(profile) {}
@@ -123,11 +118,11 @@ void PermissionsUpdater::NotifyPermissionsUpdated(
 
   if (event_type == REMOVED) {
     reason = UpdatedExtensionPermissionsInfo::REMOVED;
-    event_name = kOnRemoved;
+    event_name = permissions::OnRemoved::kEventName;
   } else {
     CHECK_EQ(ADDED, event_type);
     reason = UpdatedExtensionPermissionsInfo::ADDED;
-    event_name = kOnAdded;
+    event_name = permissions::OnAdded::kEventName;
   }
 
   // Notify other APIs or interested parties.