Give the main frame a RenderWidget.

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index a04779a089a83550d8d2f3cd01fdcd001130680a..f4df87df854ee574f87fdcde0a39fafbe2142fb9 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -932,24 +932,26 @@ void RenderFrameHostImpl::OnDidDropNavigation() {
 }
 
 RenderWidgetHostImpl* RenderFrameHostImpl::GetRenderWidgetHost() {
-  if (render_widget_host_)
-    return render_widget_host_;
-
   // TODO(kenrb): When RenderViewHost no longer inherits RenderWidgetHost,
   // we can remove this fallback. Currently it is only used for the main
   // frame.
   if (!GetParent())
     return static_cast<RenderWidgetHostImpl*>(render_view_host_);
 
+  if (render_widget_host_)
+    return render_widget_host_;
+
   return nullptr;
 }
 
 RenderWidgetHostView* RenderFrameHostImpl::GetView() {
-  RenderFrameHostImpl* frame = this;
-  while (frame) {
+  // TODO(dcheng): Similar to above, though the main RenderFrameHost now has a

[ncarter (slow), 2015/09/03 20:24:37]

It's not clear what "similar to above" refers to in this context. Could you make
the comment stand-alone?

[dcheng, 2015/09/03 21:29:24]

Done.

+  // RenderWidgetHost, a lot of the plumbing is still missing. Thus, for now,
+  // the main frame always uses the RVH's view. https://crbug.com/526958
+  for (RenderFrameHostImpl* frame = this; frame->GetParent();
+       frame = static_cast<RenderFrameHostImpl*>(frame->GetParent())) {
     if (frame->render_widget_host_)
       return frame->render_widget_host_->GetView();
-    frame = static_cast<RenderFrameHostImpl*>(frame->GetParent());
   }
 
   return render_view_host_->GetView();