Move Extension into extensions namespace

chrome/browser/extensions/extension_context_menu_model.h

Index: chrome/browser/extensions/extension_context_menu_model.h
diff --git a/chrome/browser/extensions/extension_context_menu_model.h b/chrome/browser/extensions/extension_context_menu_model.h
index 9144a5f379fb87f9227285a004ad8fc24aa0ca0f..d3f19a557138614ffbc87b395928d49ff9f7189e 100644
--- a/chrome/browser/extensions/extension_context_menu_model.h
+++ b/chrome/browser/extensions/extension_context_menu_model.h
@@ -12,10 +12,13 @@
 #include "ui/base/models/simple_menu_model.h"
 
 class Browser;
-class Extension;
 class ExtensionAction;
 class Profile;
 
+namespace extensions {
+class Extension;
+}
+
 // The menu model for the context menu for extension action icons (browser and
 // page actions).
 class ExtensionContextMenuModel
@@ -25,7 +28,8 @@ class ExtensionContextMenuModel
       public ExtensionUninstallDialog::Delegate {
  public:
   // Creates a menu model for the given extension action.
-  ExtensionContextMenuModel(const Extension* extension, Browser* browser);
+  ExtensionContextMenuModel(const extensions::Extension* extension,
+                            Browser* browser);
 
   // SimpleMenuModel::Delegate overrides.
   virtual bool IsCommandIdChecked(int command_id) const OVERRIDE;
@@ -47,7 +51,7 @@ class ExtensionContextMenuModel
 
   // Gets the extension we are displaying the menu for. Returns NULL if the
   // extension has been uninstalled and no longer exists.
-  const Extension* GetExtension() const;
+  const extensions::Extension* GetExtension() const;
 
   // A copy of the extension's id.
   std::string extension_id_;