Support subtitles for native fullscreen video

Source/core/rendering/RenderLayerCompositor.cpp

Index: Source/core/rendering/RenderLayerCompositor.cpp
diff --git a/Source/core/rendering/RenderLayerCompositor.cpp b/Source/core/rendering/RenderLayerCompositor.cpp
index 7073a4ba8c2b11d1f4466dbea21820cfe285792f..3b5abb5bc35cae809b50be09831ad7967fbb84a0 100644
--- a/Source/core/rendering/RenderLayerCompositor.cpp
+++ b/Source/core/rendering/RenderLayerCompositor.cpp
@@ -229,6 +229,7 @@ RenderLayerCompositor::RenderLayerCompositor(RenderView* renderView)
     , m_needsUpdateCompositingRequirementsState(false)
     , m_isTrackingRepaints(false)
     , m_rootLayerAttachment(RootLayerUnattached)
+    , m_currentFullscreenRenderer(0)
 #if !LOG_DISABLED
     , m_rootLayerUpdateCount(0)
     , m_obligateCompositedLayerCount(0)
@@ -437,6 +438,14 @@ void RenderLayerCompositor::updateCompositingLayers(CompositingUpdateType update
 
         // Host the document layer in the RenderView's root layer.
         if (isFullUpdate) {
+#if USE(NATIVE_FULLSCREEN_VIDEO)
+            if (m_currentFullscreenRenderer && m_currentFullscreenRenderer->isMedia()) {
+                RenderLayerModelObject* renderer = toRenderLayerModelObject(m_currentFullscreenRenderer);
+                RenderLayerBacking* backing = renderer->layer() ? renderer->layer()->backing() : 0;
+                childList.clear();
+                childList.append(backing->graphicsLayer());

[falken, 2013/08/24 05:25:40]

Should you check if backing was set to 0 above?

+            }
+#endif
             // Even when childList is empty, don't drop out of compositing mode if there are
             // composited layers that we didn't hit in our traversal (e.g. because of visibility:hidden).
             if (childList.isEmpty() && !hasAnyAdditionalCompositedLayers(updateRoot))
@@ -1770,6 +1779,11 @@ bool RenderLayerCompositor::requiresCompositingForTransform(RenderObject* render
 
 bool RenderLayerCompositor::requiresCompositingForVideo(RenderObject* renderer) const
 {
+#if USE(NATIVE_FULLSCREEN_VIDEO)
+    if (renderer->isVideo() && renderer == m_currentFullscreenRenderer)
+        return true;
+#endif
+
     if (!(m_compositingTriggers & ChromeClient::VideoTrigger))
         return false;
 
@@ -2641,4 +2655,15 @@ Page* RenderLayerCompositor::page() const
     return 0;
 }
 
+void RenderLayerCompositor::setCurrentFullscreenRenderer(RenderObject* renderer)
+{
+    if (renderer == m_currentFullscreenRenderer)
+        return;
+    m_currentFullscreenRenderer = renderer;
+#if USE(NATIVE_FULLSCREEN_VIDEO)
+    if (!renderer || renderer->isVideo())
+        setCompositingLayersNeedRebuild(true);
+#endif
+}
+
 } // namespace WebCore