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 37ab6486ce77cf628c34346fb539544c4960db90..d1299046db37feea9f2993daa73a95884c59dff8 100644
--- a/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/PaintLayerCompositor.cpp
@@ -170,11 +170,6 @@ static LayoutVideo* findFullscreenVideoLayoutObject(Document& document) {
       return nullptr;
     fullscreenElement = Fullscreen::fullscreenElementFrom(*contentDocument);
   }
-  // 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
-  fullscreenElement =
-      Fullscreen::currentFullScreenElementFrom(*contentDocument);
   if (!isHTMLVideoElement(fullscreenElement))
     return nullptr;
   LayoutObject* layoutObject = fullscreenElement->layoutObject();