Fix load stop events in nested OOPIFs.

When a nested OOPIF notifies its parent frame at load stop, the parent
frame wasn't always notifying its parent (e.g., the main frame).

This CL sends an IPC when the parent is remote, so that the parent can
be notified in either case.

BUG=822013
TEST=http://web.evilbit.io/loading/ should stop loading in --site-per-process

Change-Id: Ib377f5c96435d868ccf01765d242bec9b4c02e09
Reviewed-on: https://chromium-review.googlesource.com/984865
Commit-Queue: Charlie Reis <[email protected]>
Reviewed-by: Daniel Cheng <[email protected]>
Reviewed-by: Nasko Oskov <[email protected]>
Cr-Commit-Position: refs/heads/master@{#547183}
diff --git a/content/renderer/render_frame_proxy.h b/content/renderer/render_frame_proxy.h
index 4bec0360..608231ebe 100644
--- a/content/renderer/render_frame_proxy.h
+++ b/content/renderer/render_frame_proxy.h
@@ -175,6 +175,7 @@
 
   // blink::WebRemoteFrameClient implementation:
   void FrameDetached(DetachType type) override;
+  void CheckCompleted() override;
   void ForwardPostMessage(blink::WebLocalFrame* sourceFrame,
                           blink::WebRemoteFrame* targetFrame,
                           blink::WebSecurityOrigin target,