Move Extension into extensions namespace

BUG=117262
[email protected]

Review URL: https://chromiumcodereview.appspot.com/10375021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@138074 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/extension_host.h b/chrome/browser/extensions/extension_host.h
index a9aa8e23..4350872b 100644
--- a/chrome/browser/extensions/extension_host.h
+++ b/chrome/browser/extensions/extension_host.h
@@ -31,7 +31,6 @@
 #endif
 
 class Browser;
-class Extension;
 class ExtensionWindowController;
 class PrefsTabHelper;
 
@@ -41,6 +40,10 @@
 class SiteInstance;
 }
 
+namespace extensions {
+class Extension;
+}
+
 // This class is the browser component of an extension component's RenderView.
 // It handles setting up the renderer process, if needed, with special
 // privileges available to extensions.  It may have a view to be shown in the
@@ -63,7 +66,7 @@
   typedef ExtensionViewAndroid PlatformExtensionView;
 #endif
 
-  ExtensionHost(const Extension* extension,
+  ExtensionHost(const extensions::Extension* extension,
                 content::SiteInstance* site_instance,
                 const GURL& url, content::ViewType host_type);
   virtual ~ExtensionHost();
@@ -92,7 +95,7 @@
   // instantiate Browser objects.
   void CreateView(Browser* browser);
 
-  const Extension* extension() const { return extension_; }
+  const extensions::Extension* extension() const { return extension_; }
   const std::string& extension_id() const { return extension_id_; }
   content::WebContents* host_contents() const { return host_contents_.get(); }
   content::RenderViewHost* render_view_host() const;
@@ -199,7 +202,7 @@
   bool is_background_page() const { return !view(); }
 
   // The extension that we're hosting in this view.
-  const Extension* extension_;
+  const extensions::Extension* extension_;
 
   // Id of extension that we're hosting in this view.
   const std::string extension_id_;