Make GCMProfileService own GCMDriver, instead of deriving from it

chrome/browser/extensions/extension_gcm_app_handler.h

Index: chrome/browser/extensions/extension_gcm_app_handler.h
diff --git a/chrome/browser/extensions/extension_gcm_app_handler.h b/chrome/browser/extensions/extension_gcm_app_handler.h
index 7b1f0da44c508c18e4a1df5704aceaaf25a479ce..5da91b71d05697e282bc1532e4c60a9fcdca5527 100644
--- a/chrome/browser/extensions/extension_gcm_app_handler.h
+++ b/chrome/browser/extensions/extension_gcm_app_handler.h
@@ -26,6 +26,7 @@ class BrowserContext;
 }
 
 namespace gcm {
+class GCMDriver;
 class GCMProfileService;
 }
 
@@ -77,7 +78,7 @@ class ExtensionGCMAppHandler : public gcm::GCMAppHandler,
       const Extension* extension,
       UnloadedExtensionInfo::Reason reason) OVERRIDE;
 
-  gcm::GCMProfileService* GetGCMProfileService() const;
+  gcm::GCMDriver* GetGCMDriver() const;
 
   // BrowserContextKeyedAPI implementation.
   static const char* service_name() { return "ExtensionGCMAppHandler"; }