Support text track selection in video controls

third_party/WebKit/Source/core/html/shadow/MediaControls.cpp

Index: third_party/WebKit/Source/core/html/shadow/MediaControls.cpp
diff --git a/third_party/WebKit/Source/core/html/shadow/MediaControls.cpp b/third_party/WebKit/Source/core/html/shadow/MediaControls.cpp
index e78e237e5fd378fe3dd1430bdd455906ad4f9cad..359be394b98a466d6695fbb0c612579531ab2fcc 100644
--- a/third_party/WebKit/Source/core/html/shadow/MediaControls.cpp
+++ b/third_party/WebKit/Source/core/html/shadow/MediaControls.cpp
@@ -112,6 +112,7 @@ MediaControls::MediaControls(HTMLMediaElement& mediaElement)
     , m_muteButton(nullptr)
     , m_volumeSlider(nullptr)
     , m_toggleClosedCaptionsButton(nullptr)
+    , m_textTrackList(nullptr)
     , m_castButton(nullptr)
     , m_fullScreenButton(nullptr)
     , m_hideMediaControlsTimer(this, &MediaControls::hideMediaControlsTimerFired)
@@ -151,6 +152,12 @@ PassRefPtrWillBeRawPtr<MediaControls> MediaControls::create(HTMLMediaElement& me
 //     +-MediaControlMuteButtonElement                 (-webkit-media-controls-mute-button)
 //     +-MediaControlVolumeSliderElement               (-webkit-media-controls-volume-slider)
 //     +-MediaControlToggleClosedCaptionsButtonElement (-webkit-media-controls-toggle-closed-captions-button)
+//     +-MediaControlTextTrackListElement              (-internal-media-controls-text-track-list)

[philipj_slow, 2016/03/01 13:01:17]

This doesn't match initializeControls(), the MediaControlTextTrackListElement is
the last child of MediaControlPanelEnclosureElement and not a child of
MediaControlPanelElement. Not sure how to represent that in this ASCII art, it
would probably make sense to just make MediaControlTextTrackListElement a direct
child of MediaControls since it's absolutely positioned anyway. I think there's
also a better chance of doing the layout with flexbox and avoiding
position:absolute in that case.

[srivats, 2016/03/30 00:46:43]

I moved track list element under MediaControls directly. Not sure how to get rid
of position:absolute though.

+//     | {for each renderable text track}
+//       \-MediaControlTextTrackListItem               (-internal-media-controls-text-track-list-item)
+//         +-MediaControlTextTrackListItemInput        (-internal-media-controls-text-track-list-item-input)
+//         +-MediaControlTextTrackListItemCaptions     (-internal-media-controls-text-track-list-kind-captions)
+//         +-MediaControlTextTrackListItemSubtitles    (-internal-media-controls-text-track-list-kind-subtitles)
 //     +-MediaControlCastButtonElement                 (-internal-media-controls-cast-button)
 //     \-MediaControlFullscreenButtonElement           (-webkit-media-controls-fullscreen-button)
 void MediaControls::initializeControls()
@@ -225,6 +232,10 @@ void MediaControls::initializeControls()
     m_panel = panel.get();
     enclosure->appendChild(panel.release());
 
+    RefPtrWillBeRawPtr<MediaControlTextTrackListElement> textTrackList = MediaControlTextTrackListElement::create(*this);
+    m_textTrackList = textTrackList.get();
+    enclosure->appendChild(textTrackList.release());
+
     m_enclosure = enclosure.get();
     appendChild(enclosure.release());
 }
@@ -451,6 +462,14 @@ void MediaControls::refreshClosedCaptionsButtonVisibility()
     BatchedControlUpdate batch(this);
 }
 
+void MediaControls::toggleTextTrackList()
+{
+    if (!mediaElement().hasClosedCaptions())
+        return;

[philipj_slow, 2016/03/01 13:01:16]

Won't this early return leave the track list perpetually visible if all of the
text tracks are removed while the menu is open?

[srivats, 2016/03/30 00:46:43]

Good catch! I set the visibility to false before returning.

+
+    m_textTrackList->changeVisibility(m_textTrackList->isHidden());
+}
+
 void MediaControls::refreshCastButtonVisibility()
 {
     refreshCastButtonVisibilityWithoutUpdate();
@@ -750,6 +769,7 @@ DEFINE_TRACE(MediaControls)
     visitor->trace(m_fullScreenButton);
     visitor->trace(m_durationDisplay);
     visitor->trace(m_enclosure);
+    visitor->trace(m_textTrackList);
     visitor->trace(m_castButton);
     visitor->trace(m_overlayCastButton);
     HTMLDivElement::trace(visitor);