Convert push_messaging IPC msgs into mojo interfaces

content/child/child_thread_impl.h

Index: content/child/child_thread_impl.h
diff --git a/content/child/child_thread_impl.h b/content/child/child_thread_impl.h
index 29a3f7dd589482a0baa09da694c1d347bec08d3d..5717014dd0e7ac76ae670535d16c93490a955ab8 100644
--- a/content/child/child_thread_impl.h
+++ b/content/child/child_thread_impl.h
@@ -55,7 +55,6 @@ class ChildResourceMessageFilter;
 class FileSystemDispatcher;
 class InProcessChildThreadParams;
 class NotificationDispatcher;
-class PushDispatcher;
 class ServiceWorkerMessageFilter;
 class QuotaDispatcher;
 class QuotaMessageFilter;
@@ -138,10 +137,6 @@ class CONTENT_EXPORT ChildThreadImpl
     return notification_dispatcher_.get();
   }
 
-  PushDispatcher* push_dispatcher() const {
-    return push_dispatcher_.get();
-  }
-
   IPC::SyncMessageFilter* sync_message_filter() const {
     return sync_message_filter_.get();
   }
@@ -303,8 +298,6 @@ class CONTENT_EXPORT ChildThreadImpl
 
   scoped_refptr<NotificationDispatcher> notification_dispatcher_;
 
-  scoped_refptr<PushDispatcher> push_dispatcher_;
-
   std::unique_ptr<base::PowerMonitor> power_monitor_;
 
   scoped_refptr<base::SingleThreadTaskRunner> browser_process_io_runner_;