Almost finish moving context_menu_node_ from RenderViewImpl to RenderFrameImpl.

content/browser/renderer_host/render_widget_host_view_mac.h

Index: content/browser/renderer_host/render_widget_host_view_mac.h
===================================================================
--- content/browser/renderer_host/render_widget_host_view_mac.h	(revision 255719)
+++ content/browser/renderer_host/render_widget_host_view_mac.h	(working copy)
@@ -30,6 +30,7 @@
 namespace content {
 class CompositingIOSurfaceMac;
 class CompositingIOSurfaceContext;
+class RenderFrameHost;
 class RenderWidgetHostViewMac;
 class RenderWidgetHostViewMacEditCommandHelper;
 }
@@ -402,6 +403,9 @@
   gfx::Range ConvertCharacterRangeToCompositionRange(
       const gfx::Range& request_range);
 
+  // Returns the focused frame. May return NULL.
+  RenderFrameHost* GetFocusedFrame();
+
   // These member variables should be private, but the associated ObjC class
   // needs access to them and can't be made a friend.