Do not use overlays when VR shell is enabled.

media/blink/webmediaplayer_impl.cc

Index: media/blink/webmediaplayer_impl.cc
diff --git a/media/blink/webmediaplayer_impl.cc b/media/blink/webmediaplayer_impl.cc
index a105327d0635b16c4d2fdc937a2cb7a89c32fa91..a10cdad6ac8d92aad9b850646dd92d3a306f3827 100644
--- a/media/blink/webmediaplayer_impl.cc
+++ b/media/blink/webmediaplayer_impl.cc
@@ -1466,6 +1466,10 @@ void WebMediaPlayerImpl::SetDeviceScaleFactor(float scale_factor) {
   cast_impl_.SetDeviceScaleFactor(scale_factor);
 }
 
+void WebMediaPlayerImpl::SetDisableFullscreenOverlays(bool disable_overlays) {

[ddorwin, 2016/12/13 22:54:49]

It's strange to set a disable with a bool. I suggest inverting the logic.

We should also invert the member name. Most of the logic around it is negative
anyway.

[amp, 2016/12/13 23:40:02]

It was hard to follow when I first looked at it so I think I agree.  I'll look
at doing that if I move the other flag out as well, assuming the finch
experiment still makes sense with the inversion.

+  disable_fullscreen_video_overlays_ = disable_overlays;
+}
+
 void WebMediaPlayerImpl::setPoster(const blink::WebURL& poster) {
   cast_impl_.setPoster(poster);
 }