Allow MimeHandlerViewGuest be embedded inside OOPIFs

content/browser/frame_host/render_widget_host_view_child_frame.h

Index: content/browser/frame_host/render_widget_host_view_child_frame.h
diff --git a/content/browser/frame_host/render_widget_host_view_child_frame.h b/content/browser/frame_host/render_widget_host_view_child_frame.h
index 9af289d782d4706a25a8ac21a7fbc264875fc34d..42ff2bff0a990a118516b2635bda2034bda508d8 100644
--- a/content/browser/frame_host/render_widget_host_view_child_frame.h
+++ b/content/browser/frame_host/render_widget_host_view_child_frame.h
@@ -191,6 +191,14 @@ class CONTENT_EXPORT RenderWidgetHostViewChildFrame
   // to the frame tree.
   RenderWidgetHostViewBase* GetParentView();
 
+  // TODO(ekaramad): This is used for input event routing when the target of
+  // events is a RenderWidgetHostViewGuest which is embeded in an OOPIF (the

[Charlie Reis, 2016/11/02 20:47:06]

nit: embedded

[EhsanK, 2016/11/08 23:10:16]

Done.

+  // only example right now is MimeHandlerViewGuest). Same as above, this
+  // method should be removed when either direct routing is supported for RWHVG
+  // (and made a private member of RWHVG again) or RWHVG is removed entirely
+  // (https://crbug.com/533069).
+  virtual RenderWidgetHostViewBase* GetOwnerRenderWidgetHostView() const;

[Charlie Reis, 2016/11/02 20:47:06]

Why does this need to be here, if it's implemented as a NOTREACHED and only
callable on the subclass (RWHVG)?  Would it be easier to cast to RWHVG at the
only callsite (RenderWidgetHostInputEventRouter::RouteMouseEvent) and leave it
out of this class?

[EhsanK, 2016/11/08 23:10:16]

Yes, it would definitely be easier (lfg@ also suggested this earlier). I avoided
doing this originally because this is a layering violation (RWHVG lives inside
frame_host/ while RWHIER is inside renderer_host).

But as I understand this approached is being favored over adding the method to
RWHVCF esp. given that we already violate this for RWHVCF (there is also a
comment about it inside the DEPS file for renderer_host/).

I made the change and modified the DEPS file.

+
   void RegisterFrameSinkId();
   void UnregisterFrameSinkId();