Text tracks are not visible in fullscreen

https://bugs.webkit.org/show_bug.cgi?id=254473
rdar://107230116

Reviewed by Jer Noble.

When the setting "GPU Process: Block Media Layer Re-hosting" is enabled, text tracks are not visible
in fullscreen, since this depends on the ability to create a CA remote layer hosting context in the
WebProcess. This patch works around the requirement to create a CA context in the WebContent process
by sending the caption bitmaps to the UI process, where they are rendered into a CA layer, which is
inserted into the fullscreen CA layer tree. The CA layer tree in the WebContent process is still
being created, since there is some amount of caption code that depends on this in order to get the
caption bounds correct. This patch also sets the flag "GPU Process: Block Media Layer Re-hosting" to
true, which is required to be able to block CARenderServer in the WebContent process' sandbox.
Layout test runs on iOS simulator on the bots showed some flaky timeouts of the test
webrtc/video-rotation.html. Looking at test history, this test has already been flaky on simulator.
This patch is about captions in fullscreen, so I don't think it will affect this test, although it
cannot be ruled out. I marked the test as flaky. This is being tracked in webkit.org/b/254872.

* LayoutTests/platform/ios-simulator-wk2/TestExpectations:
* Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml:
* Source/WebCore/WebCore.xcodeproj/project.pbxproj:
* Source/WebCore/html/shadow/MediaControlTextTrackContainerElement.cpp:
(WebCore::MediaControlTextTrackContainerElement::updateTextTrackRepresentationIfNeeded):
* Source/WebCore/platform/graphics/TextTrackRepresentation.cpp:
(WebCore::TextTrackRepresentation::create):
* Source/WebCore/platform/graphics/TextTrackRepresentation.h:
* Source/WebCore/platform/graphics/cocoa/TextTrackRepresentationCocoa.h:
* Source/WebCore/platform/graphics/cocoa/TextTrackRepresentationCocoa.mm:
(WebCore::TextTrackRepresentation::create):
(WebCore::TextTrackRepresentationCocoa::representationFactory):
* Source/WebCore/platform/ios/VideoFullscreenInterfaceAVKit.h:
* Source/WebCore/platform/ios/VideoFullscreenInterfaceAVKit.mm:
(VideoFullscreenInterfaceAVKit::textTrackRepresentationUpdate):
(VideoFullscreenInterfaceAVKit::textTrackRepresentationSetContentsScale):
(VideoFullscreenInterfaceAVKit::textTrackRepresentationSetHidden):
(VideoFullscreenInterfaceAVKit::captionsLayer):
(VideoFullscreenInterfaceAVKit::setCaptionsFrame):
(VideoFullscreenInterfaceAVKit::setupCaptionsLayer):
(VideoFullscreenInterfaceAVKit::removeCaptionsLayer):
* Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.h:
* Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.messages.in:
* Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.mm:
(WebKit::VideoFullscreenManagerProxy::createLayerHostViewWithID):
(WebKit::VideoFullscreenManagerProxy::textTrackRepresentationUpdate):
(WebKit::VideoFullscreenManagerProxy::textTrackRepresentationSetContentsScale):
(WebKit::VideoFullscreenManagerProxy::textTrackRepresentationSetHidden):
(WebKit::VideoFullscreenManagerProxy::didCleanupFullscreen):
(WebKit::VideoFullscreenManagerProxy::setVideoLayerFrame):
* Source/WebKit/WebKit.xcodeproj/project.pbxproj:
* Source/WebKit/WebProcess/cocoa/VideoFullscreenManager.h:
(WebKit::VideoFullscreenInterfaceContext::rootLayer const):
(WebKit::VideoFullscreenInterfaceContext::setRootLayer):
* Source/WebKit/WebProcess/cocoa/VideoFullscreenManager.mm:
(WebKit::VideoFullscreenManager::createModelAndInterface):
(WebKit::VideoFullscreenManager::ensureModelAndInterface):
(WebKit::VideoFullscreenManager::setupRemoteLayerHosting):
(WebKit::VideoFullscreenManager::enterVideoFullscreenForVideoElement):
(WebKit::VideoFullscreenManager::requestVideoContentLayer):
(WebKit::VideoFullscreenManager::didCleanupFullscreen):
(WebKit::VideoFullscreenManager::setVideoLayerFrameFenced):
(WebKit::VideoFullscreenManager::updateTextTrackRepresentationForVideoElement):
(WebKit::VideoFullscreenManager::setTextTrackRepresentationContentScaleForVideoElement):
(WebKit::VideoFullscreenManager::setTextTrackRepresentationIsHiddenForVideoElement):

Canonical link: https://commits.webkit.org/262487@main

LayoutTests/platform/ios-simulator-wk2/TestExpectations

@@ -164,3 +164,5 @@ webkit.org/b/236926 webrtc/vp9-profile2.html [ Timeout Pass ]
 imported/w3c/web-platform-tests/html/semantics/embedded-content/the-img-element/adopt-from-image-document.html [ Pass ImageOnlyFailure ]
 
 webkit.org/b/242748 [ Release arm64 ] css3/color-filters/svg/color-filter-inline-svg.html [ ImageOnlyFailure ]
+
+webkit.org/b/254872 webrtc/video-rotation.html [ Pass Timeout ]

Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml

@@ -780,8 +780,7 @@ BlockMediaLayerRehostingInWebContentProcess:
     WebKitLegacy:
       default: false
     WebKit:
-      "PLATFORM(MAC)": true
-      default: false
+      default: true
     WebCore:
       default: false
 

Source/WebCore/WebCore.xcodeproj/project.pbxproj

@@ -5592,6 +5592,7 @@
 		E35B8C6228DD204100293D90 /* LoadableImportMap.h in Headers */ = {isa = PBXBuildFile; fileRef = E35B8C5E28DD202D00293D90 /* LoadableImportMap.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E35B907F23F60A50000011FF /* LocalizedDeviceModel.h in Headers */ = {isa = PBXBuildFile; fileRef = E35B907C23F60677000011FF /* LocalizedDeviceModel.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E364321C25D37A6700F90E2A /* ModuleScriptLoader.h in Headers */ = {isa = PBXBuildFile; fileRef = E364321A25D37A6600F90E2A /* ModuleScriptLoader.h */; settings = {ATTRIBUTES = (Private, ); }; };
+		E36A00E429CF7B8600AC4E8A /* TextTrackRepresentationCocoa.h in Headers */ = {isa = PBXBuildFile; fileRef = 526724F21CB2FDF60075974D /* TextTrackRepresentationCocoa.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E36D701F27B7200C006531B7 /* AttachmentElementClient.h in Headers */ = {isa = PBXBuildFile; fileRef = E36D701B27B70B23006531B7 /* AttachmentElementClient.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E36D702027B72013006531B7 /* EmptyAttachmentElementClient.h in Headers */ = {isa = PBXBuildFile; fileRef = E36D701E27B71F04006531B7 /* EmptyAttachmentElementClient.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E377FE4D1DADE16500CDD025 /* NodeConstants.h in Headers */ = {isa = PBXBuildFile; fileRef = E3D049931DADC04500718F3C /* NodeConstants.h */; settings = {ATTRIBUTES = (Private, ); }; };
@@ -40186,6 +40187,7 @@
 				B1AD4E7413A12A4600846B27 /* TextTrackLoader.h in Headers */,
 				CD8B5A49180E138B008B8E65 /* TextTrackMediaSource.h in Headers */,
 				1DF7E81F251A9E0600DB8F61 /* TextTrackRepresentation.h in Headers */,
+				E36A00E429CF7B8600AC4E8A /* TextTrackRepresentationCocoa.h in Headers */,
 				BE0787A829B2279E0067473E /* TextTransform.h in Headers */,
 				1C73A7132185757E004CCEA5 /* TextUnderlineOffset.h in Headers */,
 				29FAF4B6195AB08900A522DC /* TextUndoInsertionMarkupMac.h in Headers */,

Source/WebCore/html/shadow/MediaControlTextTrackContainerElement.cpp

@@ -298,7 +298,7 @@ void MediaControlTextTrackContainerElement::updateTextTrackRepresentationIfNeede
     if (!m_textTrackRepresentation) {
         ALWAYS_LOG(LOGIDENTIFIER);
 
-        m_textTrackRepresentation = TextTrackRepresentation::create(*this);
+        m_textTrackRepresentation = TextTrackRepresentation::create(*this, *m_mediaElement);
         if (document().page())
             m_textTrackRepresentation->setContentScale(document().page()->deviceScaleFactor());
         m_mediaElement->setTextTrackRepresentation(m_textTrackRepresentation.get());

Source/WebCore/platform/graphics/TextTrackRepresentation.cpp

@@ -44,7 +44,7 @@ class NullTextTrackRepresentation : public TextTrackRepresentation {
 
 #if !(PLATFORM(IOS_FAMILY) || (PLATFORM(MAC) && ENABLE(VIDEO_PRESENTATION_MODE)))
 
-std::unique_ptr<TextTrackRepresentation> TextTrackRepresentation::create(TextTrackRepresentationClient&)
+std::unique_ptr<TextTrackRepresentation> TextTrackRepresentation::create(TextTrackRepresentationClient&, HTMLMediaElement&)
 {
     return makeUnique<NullTextTrackRepresentation>();
 }

Source/WebCore/platform/graphics/TextTrackRepresentation.h

@@ -32,6 +32,7 @@
 
 namespace WebCore {
 
+class HTMLMediaElement;
 class Image;
 class IntRect;
 
@@ -46,7 +47,7 @@ class TextTrackRepresentationClient {
 class TextTrackRepresentation {
     WTF_MAKE_FAST_ALLOCATED;
 public:
-    static std::unique_ptr<TextTrackRepresentation> create(TextTrackRepresentationClient&);
+    static std::unique_ptr<TextTrackRepresentation> create(TextTrackRepresentationClient&, HTMLMediaElement&);
 
     virtual ~TextTrackRepresentation() = default;
 

Source/WebCore/platform/graphics/cocoa/TextTrackRepresentationCocoa.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2012-2023 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -23,8 +23,7 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef TextTrackRepresentationCocoa_h
-#define TextTrackRepresentationCocoa_h
+#pragma once
 
 #if (PLATFORM(IOS_FAMILY) || (PLATFORM(MAC) && ENABLE(VIDEO_PRESENTATION_MODE))) && ENABLE(VIDEO)
 
@@ -37,30 +36,37 @@
 
 namespace WebCore {
 
-class TextTrackRepresentationCocoa final : public TextTrackRepresentation, public CanMakeWeakPtr<TextTrackRepresentationCocoa, WeakPtrFactoryInitialization::Eager> {
+class HTMLMediaElement;
+
+class TextTrackRepresentationCocoa : public TextTrackRepresentation, public CanMakeWeakPtr<TextTrackRepresentationCocoa, WeakPtrFactoryInitialization::Eager> {
 public:
-    explicit TextTrackRepresentationCocoa(TextTrackRepresentationClient&);
-    virtual ~TextTrackRepresentationCocoa();
+    WEBCORE_EXPORT explicit TextTrackRepresentationCocoa(TextTrackRepresentationClient&);
+    WEBCORE_EXPORT virtual ~TextTrackRepresentationCocoa();
 
     TextTrackRepresentationClient& client() const { return m_client; }
 
     PlatformLayer* platformLayer() final { return m_layer.get(); }
 
-    IntRect bounds() const final;
+    WEBCORE_EXPORT IntRect bounds() const override;
     void boundsChanged();
 
-private:
-    void update() final;
-    void setContentScale(float) final;
-    void setHidden(bool) const final;
+    using TextTrackRepresentationFactory = WTF::Function<std::unique_ptr<TextTrackRepresentation>(TextTrackRepresentationClient&, HTMLMediaElement&)>;
+
+    WEBCORE_EXPORT static TextTrackRepresentationFactory& representationFactory();
+
+protected:
+    // TextTrackRepresentation
+    WEBCORE_EXPORT void update() override;
+    WEBCORE_EXPORT void setContentScale(float) override;
+    WEBCORE_EXPORT void setHidden(bool) const override;
 
     TextTrackRepresentationClient& m_client;
+
+private:
     RetainPtr<CALayer> m_layer;
     RetainPtr<WebCoreTextTrackRepresentationCocoaHelper> m_delegate;
 };
 
 }
 
 #endif // (PLATFORM(IOS_FAMILY) || (PLATFORM(MAC) && ENABLE(VIDEO_PRESENTATION_MODE))) && ENABLE(VIDEO)
-
-#endif // TextTrackRepresentationCocoa_h

Source/WebCore/platform/graphics/cocoa/TextTrackRepresentationCocoa.mm

@@ -107,11 +107,19 @@ - (id)actionForLayer:(CALayer *)layer forKey:(NSString *)event
 
 namespace WebCore {
 
-std::unique_ptr<TextTrackRepresentation> TextTrackRepresentation::create(TextTrackRepresentationClient& client)
+std::unique_ptr<TextTrackRepresentation> TextTrackRepresentation::create(TextTrackRepresentationClient& client, HTMLMediaElement& mediaElement)
 {
+    if (TextTrackRepresentationCocoa::representationFactory())
+        return TextTrackRepresentationCocoa::representationFactory()(client, mediaElement);
     return makeUnique<TextTrackRepresentationCocoa>(client);
 }
 
+TextTrackRepresentationCocoa::TextTrackRepresentationFactory& TextTrackRepresentationCocoa::representationFactory()
+{
+    static NeverDestroyed<TextTrackRepresentationFactory> factory;
+    return factory.get();
+}
+
 TextTrackRepresentationCocoa::TextTrackRepresentationCocoa(TextTrackRepresentationClient& client)
     : m_client(client)
     , m_layer(adoptNS([[CALayer alloc] init]))

Source/WebCore/platform/ios/VideoFullscreenInterfaceAVKit.h

@@ -31,6 +31,7 @@
 #include "EventListener.h"
 #include "HTMLMediaElementEnums.h"
 #include "MediaPlayerIdentifier.h"
+#include "PlatformImage.h"
 #include "PlatformLayer.h"
 #include "PlaybackSessionInterfaceAVKit.h"
 #include "VideoFullscreenModel.h"
@@ -162,6 +163,15 @@ class VideoFullscreenInterfaceAVKit final
     WEBCORE_EXPORT AVPlayerViewController *avPlayerViewController() const;
     WebAVPlayerController *playerController() const;
 
+    WEBCORE_EXPORT void textTrackRepresentationUpdate(PlatformImagePtr textTrack);
+    WEBCORE_EXPORT void textTrackRepresentationSetContentsScale(float scale);
+    WEBCORE_EXPORT void textTrackRepresentationSetHidden(bool hidden);
+
+    WEBCORE_EXPORT CALayer* captionsLayer();
+    WEBCORE_EXPORT void setCaptionsFrame(const CGRect&);
+    WEBCORE_EXPORT void setupCaptionsLayer(CALayer* parent, const WebCore::FloatSize&);
+    WEBCORE_EXPORT void removeCaptionsLayer();
+
 private:
     WEBCORE_EXPORT VideoFullscreenInterfaceAVKit(PlaybackSessionInterfaceAVKit&);
 
@@ -236,6 +246,8 @@ class VideoFullscreenInterfaceAVKit final
     bool m_shouldIgnoreAVKitCallbackAboutExitFullscreenReason { false };
     bool m_enteringPictureInPicture { false };
     bool m_exitingPictureInPicture { false };
+
+    RetainPtr<CALayer> m_captionsLayer;
 };
 
 }

Source/WebCore/platform/ios/VideoFullscreenInterfaceAVKit.mm

@@ -1533,6 +1533,52 @@ - (void)removeFromParentViewController
     return hasMode(WebCore::HTMLMediaElementEnums::VideoFullscreenModePictureInPicture) && [playerController() isPlaying];
 }
 
+void VideoFullscreenInterfaceAVKit::textTrackRepresentationUpdate(PlatformImagePtr textTrack)
+{
+    [m_captionsLayer setContents:(__bridge id)textTrack.get()];
+}
+
+void VideoFullscreenInterfaceAVKit::textTrackRepresentationSetContentsScale(float scale)
+{
+    [m_captionsLayer setContentsScale:scale];
+}
+
+void VideoFullscreenInterfaceAVKit::textTrackRepresentationSetHidden(bool hidden)
+{
+    [m_captionsLayer setHidden:hidden];
+}
+
+CALayer *VideoFullscreenInterfaceAVKit::captionsLayer()
+{
+    if (!m_captionsLayer)
+        m_captionsLayer = adoptNS([[CALayer alloc] init]);
+    return m_captionsLayer.get();
+}
+
+void VideoFullscreenInterfaceAVKit::setCaptionsFrame(const CGRect& frame)
+{
+    [captionsLayer() setFrame:frame];
+}
+
+void VideoFullscreenInterfaceAVKit::setupCaptionsLayer(CALayer* parent, const WebCore::FloatSize& initialSize)
+{
+    [captionsLayer() removeFromSuperlayer];
+    [parent addSublayer:captionsLayer()];
+
+    [CATransaction begin];
+    [CATransaction setDisableActions:YES];
+    captionsLayer().zPosition = FLT_MAX;
+    [captionsLayer() setAnchorPoint:CGPointZero];
+    [captionsLayer() setBounds:CGRectMake(0, 0, initialSize.width(), initialSize.height())];
+    [CATransaction commit];
+}
+
+void VideoFullscreenInterfaceAVKit::removeCaptionsLayer()
+{
+    [m_captionsLayer removeFromSuperlayer];
+    m_captionsLayer = nullptr;
+}
+
 static std::optional<bool> isPictureInPictureSupported;
 
 void WebCore::setSupportsPictureInPicture(bool isSupported)

Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.h

@@ -213,6 +213,9 @@ class VideoFullscreenManagerProxy : public RefCounted<VideoFullscreenManagerProx
     void preparedToExitFullscreen(PlaybackSessionContextIdentifier);
     void exitFullscreenWithoutAnimationToMode(PlaybackSessionContextIdentifier, WebCore::HTMLMediaElementEnums::VideoFullscreenMode);
     void setPlayerIdentifier(PlaybackSessionContextIdentifier, std::optional<WebCore::MediaPlayerIdentifier>);
+    void textTrackRepresentationUpdate(PlaybackSessionContextIdentifier, const ShareableBitmapHandle& textTrack);
+    void textTrackRepresentationSetContentsScale(PlaybackSessionContextIdentifier, float scale);
+    void textTrackRepresentationSetHidden(PlaybackSessionContextIdentifier, bool hidden);
 
     // Messages to VideoFullscreenManager
     void requestFullscreenMode(PlaybackSessionContextIdentifier, WebCore::HTMLMediaElementEnums::VideoFullscreenMode, bool finishedWithMedia = false);

Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.messages.in

@@ -36,5 +36,9 @@ messages -> VideoFullscreenManagerProxy {
     PreparedToReturnToInline(WebKit::PlaybackSessionContextIdentifier contextId, bool visible, WebCore::FloatRect inlineRect)
     PreparedToExitFullscreen(WebKit::PlaybackSessionContextIdentifier contextId)
     ExitFullscreenWithoutAnimationToMode(WebKit::PlaybackSessionContextIdentifier contextId, WebCore::HTMLMediaElementEnums::VideoFullscreenMode videoFullscreenMode)
+
+    TextTrackRepresentationUpdate(WebKit::PlaybackSessionContextIdentifier contextId, WebKit::ShareableBitmapHandle textTrack)
+    TextTrackRepresentationSetContentsScale(WebKit::PlaybackSessionContextIdentifier contextId, float scale)
+    TextTrackRepresentationSetHidden(WebKit::PlaybackSessionContextIdentifier contextId, bool hidden)
 }
 #endif

Source/WebKit/UIProcess/Cocoa/VideoFullscreenManagerProxy.mm

@@ -598,6 +598,11 @@ - (BOOL)prefersStatusBarHidden
     }
     [view layer].frame = CGRectMake(0, 0, initialSize.width(), initialSize.height());
     [view setContextID:videoLayerID];
+
+#if PLATFORM(IOS_FAMILY)
+    interface->setupCaptionsLayer([view layer], initialSize);
+#endif
+
     return view;
 }
 
@@ -855,6 +860,32 @@ - (BOOL)prefersStatusBarHidden
     ensureInterface(contextId).preparedToExitFullscreen();
 }
 
+void VideoFullscreenManagerProxy::textTrackRepresentationUpdate(PlaybackSessionContextIdentifier contextId, const ShareableBitmapHandle& textTrack)
+{
+#if PLATFORM(IOS_FAMILY)
+    auto bitmap = ShareableBitmap::create(textTrack);
+    if (!bitmap)
+        return;
+
+    auto platformImage = bitmap->createPlatformImage();
+    ensureInterface(contextId).textTrackRepresentationUpdate(platformImage);
+#endif
+}
+
+void VideoFullscreenManagerProxy::textTrackRepresentationSetContentsScale(PlaybackSessionContextIdentifier contextId, float scale)
+{
+#if PLATFORM(IOS_FAMILY)
+    ensureInterface(contextId).textTrackRepresentationSetContentsScale(scale);
+#endif
+}
+
+void VideoFullscreenManagerProxy::textTrackRepresentationSetHidden(PlaybackSessionContextIdentifier contextId, bool hidden)
+{
+#if PLATFORM(IOS_FAMILY)
+    ensureInterface(contextId).textTrackRepresentationSetHidden(hidden);
+#endif
+}
+
 #pragma mark Messages to VideoFullscreenManager
 
 void VideoFullscreenManagerProxy::callCloseCompletionHandlers()
@@ -966,6 +997,9 @@ - (BOOL)prefersStatusBarHidden
     auto& [model, interface] = ensureModelAndInterface(contextId);
 
     [model->layerHostView() removeFromSuperview];
+#if PLATFORM(IOS_FAMILY)
+    interface->removeCaptionsLayer();
+#endif
     if (auto playerLayer = model->playerLayer()) {
         // Return the video layer to the player layer
         auto videoView = model->layerHostView();
@@ -986,7 +1020,9 @@ - (BOOL)prefersStatusBarHidden
 void VideoFullscreenManagerProxy::setVideoLayerFrame(PlaybackSessionContextIdentifier contextId, WebCore::FloatRect frame)
 {
 #if PLATFORM(IOS_FAMILY)
+    auto& [model, interface] = ensureModelAndInterface(contextId);
     auto fenceSendRight = MachSendRight::adopt([UIWindow _synchronizeDrawingAcrossProcesses]);
+    interface->setCaptionsFrame(CGRectMake(0, 0, frame.width(), frame.height()));
 #else
     MachSendRight fenceSendRight;
     if (DrawingAreaProxy* drawingArea = m_page->drawingArea())

Source/WebKit/WebKit.xcodeproj/project.pbxproj

@@ -2113,6 +2113,7 @@
 		E1E552C516AE065F004ED653 /* SandboxInitializationParameters.h in Headers */ = {isa = PBXBuildFile; fileRef = E1E552C316AE065E004ED653 /* SandboxInitializationParameters.h */; };
 		E1EE53E311F8CFC000CCBEE4 /* InjectedBundlePageEditorClient.h in Headers */ = {isa = PBXBuildFile; fileRef = E1EE53DC11F8CF9F00CCBEE4 /* InjectedBundlePageEditorClient.h */; };
 		E326E357284E580E00157372 /* AuxiliaryProcessProxyCocoa.mm in Sources */ = {isa = PBXBuildFile; fileRef = E326E356284E580E00157372 /* AuxiliaryProcessProxyCocoa.mm */; };
+		E36A00E329CF7AC000AC4E8A /* TextTrackRepresentationCocoa.mm in Sources */ = {isa = PBXBuildFile; fileRef = E36A00E229CF7AC000AC4E8A /* TextTrackRepresentationCocoa.mm */; };
 		E36FF00327F36FBD004BE21A /* SandboxStateVariables.h in Headers */ = {isa = PBXBuildFile; fileRef = E36FF00127F36FBD004BE21A /* SandboxStateVariables.h */; };
 		E3816B3D27E2463A005EAFC0 /* WebMockContentFilterManager.cpp in Sources */ = {isa = PBXBuildFile; fileRef = E3816B3B27E24639005EAFC0 /* WebMockContentFilterManager.cpp */; };
 		E3816B3E27E2463A005EAFC0 /* WebMockContentFilterManager.h in Headers */ = {isa = PBXBuildFile; fileRef = E3816B3C27E24639005EAFC0 /* WebMockContentFilterManager.h */; };
@@ -2125,6 +2126,7 @@
 		E38A1FC023A551BF00D2374F /* UserInterfaceIdiom.mm in Sources */ = {isa = PBXBuildFile; fileRef = E38A1FBF23A551BF00D2374F /* UserInterfaceIdiom.mm */; };
 		E39628DD23960CC600658ECD /* WebDeviceOrientationUpdateProvider.h in Headers */ = {isa = PBXBuildFile; fileRef = E39628DB23960CC500658ECD /* WebDeviceOrientationUpdateProvider.h */; };
 		E39628DE23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp in Sources */ = {isa = PBXBuildFile; fileRef = E39628DC23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp */; };
+		E3C6727329D4A3AD00AD4452 /* TextTrackRepresentationCocoa.h in Headers */ = {isa = PBXBuildFile; fileRef = E36A00E129CF4EBA00AC4E8A /* TextTrackRepresentationCocoa.h */; };
 		E3CAAA442413279900CED2E2 /* AccessibilitySupportSPI.h in Headers */ = {isa = PBXBuildFile; fileRef = E3CAAA432413278A00CED2E2 /* AccessibilitySupportSPI.h */; };
 		E413F59D1AC1ADC400345360 /* NetworkCacheEntry.h in Headers */ = {isa = PBXBuildFile; fileRef = E413F59B1AC1ADB600345360 /* NetworkCacheEntry.h */; };
 		E42E06101AA7523B00B11699 /* NetworkCacheIOChannel.h in Headers */ = {isa = PBXBuildFile; fileRef = E42E060B1AA7440D00B11699 /* NetworkCacheIOChannel.h */; };
@@ -7028,6 +7030,8 @@
 		E350A7C52934F1C100A06C29 /* common.sb */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = common.sb; sourceTree = "<group>"; };
 		E350A7C82934F75F00A06C29 /* common.sb */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = common.sb; sourceTree = "<group>"; };
 		E350A7DF29364D3800A06C29 /* util.sb */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = util.sb; sourceTree = "<group>"; };
+		E36A00E129CF4EBA00AC4E8A /* TextTrackRepresentationCocoa.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = TextTrackRepresentationCocoa.h; sourceTree = "<group>"; };
+		E36A00E229CF7AC000AC4E8A /* TextTrackRepresentationCocoa.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = TextTrackRepresentationCocoa.mm; sourceTree = "<group>"; };
 		E36D701A27B709ED006531B7 /* WebAttachmentElementClient.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = WebAttachmentElementClient.h; sourceTree = "<group>"; };
 		E36D701D27B718EF006531B7 /* WebAttachmentElementClient.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = WebAttachmentElementClient.cpp; sourceTree = "<group>"; };
 		E36FF00127F36FBD004BE21A /* SandboxStateVariables.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SandboxStateVariables.h; sourceTree = "<group>"; };
@@ -11376,6 +11380,8 @@
 				416008B125DA86B900E892FE /* RemoteRealtimeMediaSourceProxy.h */,
 				418FCBE3271049DB00F96ECA /* RemoteRealtimeVideoSource.cpp */,
 				418FCBE4271049DC00F96ECA /* RemoteRealtimeVideoSource.h */,
+				E36A00E129CF4EBA00AC4E8A /* TextTrackRepresentationCocoa.h */,
+				E36A00E229CF7AC000AC4E8A /* TextTrackRepresentationCocoa.mm */,
 				CD491B051E70D05F00009066 /* UserMediaCaptureManager.cpp */,
 				CD491B061E70D05F00009066 /* UserMediaCaptureManager.h */,
 				CD491B0A1E732D1200009066 /* UserMediaCaptureManager.messages.in */,
@@ -14632,6 +14638,7 @@
 				53CFBBC82224D1B500266546 /* TextCheckerCompletion.h in Headers */,
 				1A5E4DA412D3BD3D0099A2BB /* TextCheckerState.h in Headers */,
 				CE1A0BD71A48E6C60054EF74 /* TextInputSPI.h in Headers */,
+				E3C6727329D4A3AD00AD4452 /* TextTrackRepresentationCocoa.h in Headers */,
 				1AAF263914687C39004A1E8A /* TiledCoreAnimationDrawingArea.h in Headers */,
 				1AF05D8714688348008B1E81 /* TiledCoreAnimationDrawingAreaProxy.h in Headers */,
 				F48570A32644BEC500C05F71 /* Timeout.h in Headers */,
@@ -16981,6 +16988,7 @@
 				93D6B782254CCCF40058DD3A /* SpeechRecognitionServerMessageReceiver.cpp in Sources */,
 				1A334DED16DE8F88006A8E38 /* StorageAreaMapMessageReceiver.cpp in Sources */,
 				5CAAA85029BFBE99003340AE /* TCCSoftLink.mm in Sources */,
+				E36A00E329CF7AC000AC4E8A /* TextTrackRepresentationCocoa.mm in Sources */,
 				2D11B7512126A282006F8878 /* UnifiedSource1-mm.mm in Sources */,
 				7B9FC5F028ABB557007570E7 /* UnifiedSource1.cpp in Sources */,
 				2D11B7532126A282006F8878 /* UnifiedSource2-mm.mm in Sources */,