[Cleanup] Rename Hidden to Background in WMPI.

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 0ab7b54d2cfdf4ee3dc09c257d782eea66e0c312..da39318d924ab3816ffe1bf0136aac04b38e74de 100644
--- a/media/blink/webmediaplayer_impl.cc
+++ b/media/blink/webmediaplayer_impl.cc
@@ -206,7 +206,7 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
       opaque_(false),
       playback_rate_(0.0),
       paused_(true),
-      paused_when_hidden_(false),
+      paused_when_background_(false),
       seeking_(false),
       pending_suspend_resume_cycle_(false),
       ended_(false),
@@ -453,8 +453,8 @@ void WebMediaPlayerImpl::pause() {
   // paused state.
   paused_ = true;
 
-  // No longer paused because it was hidden.
-  paused_when_hidden_ = false;
+  // No longer paused because it was backgrounded.
+  paused_when_background_ = false;
 
 #if defined(OS_ANDROID)  // WMPI_CAST
   if (isRemote()) {
@@ -1117,8 +1117,8 @@ void WebMediaPlayerImpl::OnPipelineSeeked(bool time_updated) {
   // actions from artificially inflating the underflow count.
   underflow_count_ = 0;
 
-  // Background video optimizations are delayed when shown/hidden if pipeline
-  // is seeking.
+  // Background video optimizations are delayed when if pipeline
+  // is seeking when the video goes to the background or the foreground.
   UpdateBackgroundVideoOptimizationState();
 }
 
@@ -1405,10 +1405,8 @@ void WebMediaPlayerImpl::OnFrameHidden() {
   if (watch_time_reporter_)
     watch_time_reporter_->OnHidden();
 
-  // OnFrameHidden() can be called when frame is closed, then IsHidden() will
-  // return false, so check explicitly.
-  if (IsHidden()) {
-    if (ShouldPauseVideoWhenHidden()) {
+  if (IsBackgrounded()) {
+    if (ShouldPauseVideoWhenBackground()) {
       PauseVideoIfNeeded();
       return;
     } else {
@@ -1436,10 +1434,10 @@ void WebMediaPlayerImpl::OnFrameShown() {
     watch_time_reporter_->OnShown();
 
   // Only track the time to the first frame if playing or about to play because
-  // of being shown and only for videos we would optimize background playback
-  // for.
+  // of being foregrounded and only for videos we would optimize background
+  // playback for.
   if ((!paused_ && IsBackgroundOptimizationCandidate()) ||
-      paused_when_hidden_) {
+      paused_when_background_) {
     VideoFrameCompositor::OnNewProcessedFrameCB new_processed_frame_cb =
         BIND_TO_RENDER_LOOP1(
             &WebMediaPlayerImpl::ReportTimeFromForegroundToFirstFrame,
@@ -1450,8 +1448,8 @@ void WebMediaPlayerImpl::OnFrameShown() {
                    base::Unretained(compositor_), new_processed_frame_cb));
   }
 
-  if (paused_when_hidden_) {
-    paused_when_hidden_ = false;
+  if (paused_when_background_) {
+    paused_when_background_ = false;
     OnPlay();  // Calls UpdatePlayState() so return afterwards.
     return;
   }
@@ -1804,7 +1802,7 @@ void WebMediaPlayerImpl::UpdatePlayState() {
 #endif
 
   bool is_suspended = pipeline_controller_.IsSuspended();
-  bool is_backgrounded = IsBackgroundedSuspendEnabled() && IsHidden();
+  bool is_backgrounded = IsBackgroundedSuspendEnabled() && IsBackgrounded();
   PlayState state = UpdatePlayState_ComputePlayState(
       is_remote, is_streaming, is_suspended, is_backgrounded);
   SetDelegateState(state.delegate_state, state.is_idle);
@@ -1949,7 +1947,7 @@ WebMediaPlayerImpl::UpdatePlayState_ComputePlayState(bool is_remote,
   // the have future data state; see didLoadingProgress().
   //
   // TODO(sandersd): Make the delegate suspend idle players immediately when
-  // hidden.
+  // in the background.
   bool idle_suspended =
       !is_streaming && is_stale && paused_ && !seeking_ && !overlay_enabled_;
 
@@ -2103,9 +2101,12 @@ void WebMediaPlayerImpl::CreateWatchTimeReporter() {
     watch_time_reporter_->OnShown();
 }
 
-bool WebMediaPlayerImpl::IsHidden() const {
+bool WebMediaPlayerImpl::IsBackgrounded() const {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
+  // Nothing related to the media being in the background should matter if the
+  // frame is closed. However, the delegate might call OnFrameHidden() when
+  // closed so specifically exclude this case.
   return delegate_->IsFrameHidden() && !delegate_->IsFrameClosed();
 }
 
@@ -2123,7 +2124,7 @@ void WebMediaPlayerImpl::ActivateViewportIntersectionMonitoring(bool activate) {
   client_->activateViewportIntersectionMonitoring(activate);
 }
 
-bool WebMediaPlayerImpl::ShouldPauseVideoWhenHidden() const {
+bool WebMediaPlayerImpl::ShouldPauseVideoWhenBackground() const {
 #if !defined(OS_ANDROID)
   // On desktop, this behavior is behind the feature flag.
   if (!IsBackgroundVideoTrackOptimizationEnabled())
@@ -2134,7 +2135,7 @@ bool WebMediaPlayerImpl::ShouldPauseVideoWhenHidden() const {
   return !hasAudio() && IsBackgroundOptimizationCandidate();
 }
 
-bool WebMediaPlayerImpl::ShouldDisableVideoWhenHidden() const {
+bool WebMediaPlayerImpl::ShouldDisableVideoWhenBackground() const {
   // This optimization is behind the flag on all platforms.
   if (!IsBackgroundVideoTrackOptimizationEnabled())
     return false;
@@ -2174,8 +2175,8 @@ bool WebMediaPlayerImpl::IsBackgroundOptimizationCandidate() const {
 }
 
 void WebMediaPlayerImpl::UpdateBackgroundVideoOptimizationState() {
-  if (IsHidden()) {
-    if (ShouldPauseVideoWhenHidden())
+  if (IsBackgrounded()) {
+    if (ShouldPauseVideoWhenBackground())
       PauseVideoIfNeeded();
     else
       DisableVideoTrackIfNeeded();
@@ -2185,17 +2186,17 @@ void WebMediaPlayerImpl::UpdateBackgroundVideoOptimizationState() {
 }
 
 void WebMediaPlayerImpl::PauseVideoIfNeeded() {
-  DCHECK(IsHidden());
+  DCHECK(IsBackgrounded());
 
   // Don't pause video while the pipeline is stopped, resuming or seeking.
   // Also if the video is paused already.
   if (!pipeline_.IsRunning() || is_pipeline_resuming_ || seeking_ || paused_)
     return;
 
-  // OnPause() will set |paused_when_hidden_| to false and call
+  // OnPause() will set |paused_when_background_| to false and call
   // UpdatePlayState(), so set the flag to true after and then return.
   OnPause();
-  paused_when_hidden_ = true;
+  paused_when_background_ = true;
 }
 
 void WebMediaPlayerImpl::EnableVideoTrackIfNeeded() {
@@ -2214,13 +2215,13 @@ void WebMediaPlayerImpl::EnableVideoTrackIfNeeded() {
 }
 
 void WebMediaPlayerImpl::DisableVideoTrackIfNeeded() {
-  DCHECK(IsHidden());
+  DCHECK(IsBackgrounded());
 
   // Don't change video track while the pipeline is resuming or seeking.
   if (is_pipeline_resuming_ || seeking_)
     return;
 
-  if (!video_track_disabled_ && ShouldDisableVideoWhenHidden()) {
+  if (!video_track_disabled_ && ShouldDisableVideoWhenBackground()) {
     video_track_disabled_ = true;
     selectedVideoTrackChanged(nullptr);
   }