Make RenderFrame(Host) own a RenderWidget(Host).

content/browser/frame_host/render_frame_host_impl.h

Index: content/browser/frame_host/render_frame_host_impl.h
diff --git a/content/browser/frame_host/render_frame_host_impl.h b/content/browser/frame_host/render_frame_host_impl.h
index 7ce2fd014f2194966bc6f38413dcc6a93d17f3dc..17c9da2f576a62c41afd30dcd0c657d50602bfbf 100644
--- a/content/browser/frame_host/render_frame_host_impl.h
+++ b/content/browser/frame_host/render_frame_host_impl.h
@@ -51,6 +51,7 @@ class RenderFrameHostDelegate;
 class RenderFrameProxyHost;
 class RenderProcessHost;
 class RenderViewHostImpl;
+class RenderWidgetHostDelegate;
 class RenderWidgetHostImpl;
 struct ContextMenuParams;
 struct GlobalRequestID;
@@ -128,6 +129,9 @@ class CONTENT_EXPORT RenderFrameHostImpl
   RenderViewHostImpl* render_view_host() { return render_view_host_; }
   RenderFrameHostDelegate* delegate() { return delegate_; }
   FrameTreeNode* frame_tree_node() { return frame_tree_node_; }
+
+  void CreateRenderWidgetHost(RenderWidgetHostDelegate* delegate,

[Charlie Reis, 2014/10/01 17:01:08]

Please add a comment saying when this should be called, since we don't call it
for all frames.

[kenrb, 2014/10/01 19:27:51]

Done.

+                              bool hidden);
   // TODO(nasko): The RenderWidgetHost will be owned by RenderFrameHost in

[Charlie Reis, 2014/10/01 17:01:08]

Can we update this comment now?

[kenrb, 2014/10/01 19:27:51]

Done.

   // the future, so update this accessor to return the right pointer.
   RenderWidgetHostImpl* GetRenderWidgetHost();
@@ -438,6 +442,12 @@ class CONTENT_EXPORT RenderFrameHostImpl
   // Map from notification_id to a callback to cancel them.
   std::map<int, base::Closure> cancel_notification_callbacks_;
 
+  // RenderFrameHosts that need management of the rendering and input events
+  // for their frame subtrees require RenderWidgetHosts. This typically
+  // means main frames and frames that are rendered in different processes from

[Charlie Reis, 2014/10/01 17:01:08]

We don't use this for the main frame, do we?  Aren't we using the RVH as our
widget in that case?

[kenrb, 2014/10/01 19:27:51]

We will, but not yet. I have changed it accordingly.

+  // their parent frames.
+  scoped_ptr<RenderWidgetHostImpl> render_widget_host_impl_;

[nasko, 2014/10/01 16:37:14]

nit: it might be shorter to just drop the "impl_" part of the name, we know we
are inside content and deal with the impl classes.

[kenrb, 2014/10/01 19:27:51]

Ok.

+
   int routing_id_;
   bool is_swapped_out_;
   bool renderer_initialized_;