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

content/renderer/render_frame_impl.h

Index: content/renderer/render_frame_impl.h
diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
index bf354fffb6926602d1298bd9c90d4bf46c6943f9..57d35ba291680b4aa036eab4f4d894d3c81f6ab6 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -44,6 +44,7 @@ class TransportDIB;
 struct FrameHostMsg_AddNavigationTransitionData_Params;
 struct FrameMsg_Navigate_Params;
 struct FrameMsg_RequestNavigation_Params;
+struct FrameMsg_NewFrame_WidgetParams;
 
 namespace blink {
 class WebGeolocationClient;
@@ -118,7 +119,8 @@ class CONTENT_EXPORT RenderFrameImpl
   // through Blink and Create.
   static void CreateFrame(int routing_id,
                           int parent_routing_id,
-                          int proxy_routing_id);
+                          int proxy_routing_id,
+                          const FrameMsg_NewFrame_WidgetParams& params);
 
   // Returns the RenderFrameImpl for the given routing ID.
   static RenderFrameImpl* FromRoutingID(int routing_id);
@@ -719,6 +721,13 @@ class CONTENT_EXPORT RenderFrameImpl
   // TODO(creis): Remove this after switching to PlzNavigate.
   int proxy_routing_id_;
 
+  // Used when the RenderFrame is a local frame root; for now RenderWidgets are
+  // added only when a child frame is in a different process from its parent
+  // frame, but eventually this will also apply to top-level frames.
+  // FIXME(kenrb): Correct the above statement when top-level frames have their
+  // own RenderWidgets.
+  scoped_refptr<RenderWidget> render_widget_;
+
 #if defined(ENABLE_PLUGINS)
   // Current text input composition text. Empty if no composition is in
   // progress.