[Media, Video] Update WMPI when the pipeline gets a new average keyframe distance.

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 c19332ac2a9826eb387107789ff25f0e33758eb0..1402ec4b22c09ee687ca344c391edac52cd2b4f5 100644
--- a/media/blink/webmediaplayer_impl.cc
+++ b/media/blink/webmediaplayer_impl.cc
@@ -1402,6 +1402,10 @@ void WebMediaPlayerImpl::OnVideoOpacityChange(bool opaque) {
     video_weblayer_->layer()->SetContentsOpaque(opaque_);
 }
 
+void WebMediaPlayerImpl::OnVideoAverageKeyframeDistanceUpdate() {
+  UpdateBackgroundVideoOptimizationState();
+}
+
 void WebMediaPlayerImpl::OnFrameHidden() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());