If a page calls |window.focus()|, kick it out of fullscreen.

BUG=776418, 800056

Change-Id: I1880fe600e4814c073f247c43b1c1ac80c8fc017
Reviewed-on: https://chromium-review.googlesource.com/852378
Reviewed-by: Nasko Oskov <nasko@chromium.org>
Reviewed-by: Philip Jägenstedt <foolip@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533790}
void RenderFrameImpl::WasHidden() {
  for (auto& observer : observers_)
    observer.WasHidden();

#if BUILDFLAG(ENABLE_PLUGINS)
  for (auto* plugin : active_pepper_instances_)
    plugin->PageVisibilityChanged(false);
#endif  // ENABLE_PLUGINS

  if (GetWebFrame()->FrameWidget()) {
    GetWebFrame()->FrameWidget()->SetVisibilityState(VisibilityState());
  }
}

void RenderFrameImpl::WasHidden() {
  for (auto& observer : observers_)
    observer.WasHidden();

#if BUILDFLAG(ENABLE_PLUGINS)
  for (auto* plugin : active_pepper_instances_)
    plugin->PageVisibilityChanged(false);
#endif  // ENABLE_PLUGINS

  if (GetWebFrame()->FrameWidget()) {
    GetWebFrame()->FrameWidget()->SetVisibilityState(VisibilityState());
  }
}
