Move ExtensionEventRouter and related into extensions namespace

chrome/browser/extensions/event_names.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Constants for the event names sent to extensions.
 
-#ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_EVENT_NAMES_H_
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_EVENT_NAMES_H_
+#ifndef CHROME_BROWSER_EXTENSIONS_EVENT_NAMES_H_
+#define CHROME_BROWSER_EXTENSIONS_EVENT_NAMES_H_
 
-namespace extension_event_names {
+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[];
@@ skipping 42 matching lines @@
 // OffscreenTabs.
 extern const char kOnOffscreenTabUpdated[];
 
 #if defined(OS_CHROMEOS)
 // Bluetooth.
 extern const char kBluetoothOnAvailabilityChanged[];
 extern const char kBluetoothOnDeviceDiscovered[];
 extern const char kBluetoothOnPowerChanged[];
 #endif
 
-};  // namespace extension_event_names
+}  // namespace event_names
 
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_EVENT_NAMES_H_
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EVENT_NAMES_H_