Start pulling away notification logic from ChromeContentBrowserClient.

chrome/browser/chrome_content_browser_client.h

Index: chrome/browser/chrome_content_browser_client.h
diff --git a/chrome/browser/chrome_content_browser_client.h b/chrome/browser/chrome_content_browser_client.h
index 15f761c02ed7307da0e7dc955281a6989f0aa4b0..884ae0d3176e7cba4486f66aae173f5ee7b88a5e 100644
--- a/chrome/browser/chrome_content_browser_client.h
+++ b/chrome/browser/chrome_content_browser_client.h
@@ -180,16 +180,8 @@ class ChromeContentBrowserClient : public content::ContentBrowserClient {
                       int render_process_id,
                       int render_frame_id) override;
   content::MediaObserver* GetMediaObserver() override;
-  blink::WebNotificationPermission CheckDesktopNotificationPermission(
-      const GURL& source_origin,
-      content::ResourceContext* context,
-      int render_process_id) override;
-  void ShowDesktopNotification(
-      const content::ShowDesktopNotificationHostMsgParams& params,
-      content::BrowserContext* browser_context,
-      int render_process_id,
-      scoped_ptr<content::DesktopNotificationDelegate> delegate,
-      base::Closure* cancel_callback) override;
+  content::PlatformNotificationService* GetPlatformNotificationService()
+      override;
   void RequestPermission(
       content::PermissionType permission,
       content::WebContents* web_contents,