Reland "Sync requestFullscreen() and exitFullscreen() algorithms with the spec"

third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp

Index: third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp b/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
index 4f0e54163593627f3dcff7c8d03a2ef99d0857d6..d85c16174bba0ff74f65a4dd3739b644b9c3c85c 100644
--- a/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
@@ -171,11 +171,6 @@ static LayoutVideo* FindFullscreenVideoLayoutObject(Document& document) {
       return nullptr;
     fullscreen_element = Fullscreen::FullscreenElementFrom(*content_document);
   }
-  // Get the current fullscreen element from the document.
-  // TODO(foolip): When |currentFullScreenElementFrom| is removed, this will
-  // become a no-op and can be removed. https://crbug.com/402421
-  fullscreen_element =
-      Fullscreen::CurrentFullScreenElementFrom(*content_document);
   if (!isHTMLVideoElement(fullscreen_element))
     return nullptr;
   LayoutObject* layout_object = fullscreen_element->GetLayoutObject();