Entering Picture-In-Picture re-enables disabled video track if needed.

This CL makes sure video track disabled by video background track
optimization is re-enabled when entering Picture-in-Picture.

Bug: 949265
Change-Id: Id0cca141f262537672f49f8cdc8bc6db5c10e3dc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1556837Reviewed-by: Dan Sanders <sandersd@chromium.org>
Commit-Queue: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#721018}

media/blink/webmediaplayer_impl.cc

@@ -3351,7 +3351,7 @@ bool WebMediaPlayerImpl::IsBackgroundOptimizationCandidate() const {
 }
 
 void WebMediaPlayerImpl::UpdateBackgroundVideoOptimizationState() {
-  if (IsHidden()) {
+  if (IsHidden() && !IsInPictureInPicture()) {
     if (ShouldPausePlaybackWhenHidden()) {
       PauseVideoIfNeeded();
     } else if (update_background_status_cb_.IsCancelled()) {

media/blink/webmediaplayer_impl_unittest.cc

@@ -591,6 +591,10 @@ class WebMediaPlayerImplTest : public testing::Test {
     testing::Mock::VerifyAndClearExpectations(compositor_);
   }
 
+  void UpdateBackgroundVideoOptimizationState() {
+    wmpi_->UpdateBackgroundVideoOptimizationState();
+  }
+
   void Play() { wmpi_->Play(); }
 
   void Pause() { wmpi_->Pause(); }
@@ -2185,6 +2189,22 @@ TEST_P(WebMediaPlayerImplBackgroundBehaviorTest, AudioVideo) {
     // provides much of a benefit at the moment, this is being ignored.
     EXPECT_TRUE(IsDisableVideoTrackPending());
   }
+
+  // If the video wasn't in Picture-in-Picture and didn't pause, trigger
+  // Picture-in-Picture. It should disable optimizations.
+  if (!IsPictureInPictureOn() && IsDisableVideoTrackPending()) {
+    EXPECT_CALL(client_, DisplayType())
+        .WillRepeatedly(
+            Return(blink::WebMediaPlayer::DisplayType::kPictureInPicture));
+
+    EXPECT_CALL(client_, OnPictureInPictureStateChange()).Times(1);
+    wmpi_->OnSurfaceIdUpdated(surface_id_);
+
+    UpdateBackgroundVideoOptimizationState();
+
+    EXPECT_FALSE(IsVideoTrackDisabled());
+    EXPECT_FALSE(IsDisableVideoTrackPending());
+  }
 }
 
 INSTANTIATE_TEST_SUITE_P(