Revert "Always activate MojoApplicationHost"

content/browser/renderer_host/render_process_host_impl.h

Index: content/browser/renderer_host/render_process_host_impl.h
diff --git a/content/browser/renderer_host/render_process_host_impl.h b/content/browser/renderer_host/render_process_host_impl.h
index 0639b405856765ec251a21314e36585efdfbf705..a25fd444d474711a694dac994eea0273572ccd12 100644
--- a/content/browser/renderer_host/render_process_host_impl.h
+++ b/content/browser/renderer_host/render_process_host_impl.h
@@ -252,6 +252,9 @@ class CONTENT_EXPORT RenderProcessHostImpl
   // immediately after receiving response headers.
   void ResumeResponseDeferredAtStart(const GlobalRequestID& request_id);
 
+  // Activates Mojo for this process. Does nothing if Mojo is already activated.
+  void EnsureMojoActivated();
+
  protected:
   // A proxy for our IPC::Channel that lives on the IO thread (see
   // browser_process.h)
@@ -276,6 +279,7 @@ class CONTENT_EXPORT RenderProcessHostImpl
  private:
   friend class VisitRelayingRenderProcessHost;
 
+  void MaybeActivateMojo();
   bool ShouldUseMojoChannel() const;
   scoped_ptr<IPC::ChannelProxy> CreateChannelProxy(
       const std::string& channel_id);
@@ -323,6 +327,7 @@ class CONTENT_EXPORT RenderProcessHostImpl
 #endif
 
   scoped_ptr<MojoApplicationHost> mojo_application_host_;
+  bool mojo_activation_required_;
 
   // The registered IPC listener objects. When this list is empty, we should
   // delete ourselves.