Correctly reset FP in RFHI whenever origin changes

Bug: 713364
Change-Id: Id8bb923750e20f3db6fc9358b1d44120513ac95f

CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Change-Id: Id8bb923750e20f3db6fc9358b1d44120513ac95f
Reviewed-on: https://chromium-review.googlesource.com/482380
Commit-Queue: Ian Clelland <iclelland@chromium.org>
Reviewed-by: Charles Reis <creis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#466778}
RenderWidgetHostImpl* RenderFrameHostImpl::GetRenderWidgetHost() {
  RenderFrameHostImpl* frame = this;
  while (frame) {
    if (frame->render_widget_host_)
      return frame->render_widget_host_;
    frame = frame->GetParent();
  }

  NOTREACHED();
  return nullptr;
}

RenderWidgetHostImpl* RenderFrameHostImpl::GetRenderWidgetHost() {
  RenderFrameHostImpl* frame = this;
  while (frame) {
    if (frame->render_widget_host_)
      return frame->render_widget_host_;
    frame = frame->GetParent();
  }

  NOTREACHED();
  return nullptr;
}
