Don't show video fullscreen until DidEnterFullscreen() is called

Source/web/FullscreenController.cpp

Index: Source/web/FullscreenController.cpp
diff --git a/Source/web/FullscreenController.cpp b/Source/web/FullscreenController.cpp
index 44a6b33be6f5178601947040ac3f79372139e78b..7cac4ff07499a4288b0cd1cd7186cc88ad8306a8 100644
--- a/Source/web/FullscreenController.cpp
+++ b/Source/web/FullscreenController.cpp
@@ -89,8 +89,16 @@ void FullscreenController::didEnterFullScreen()
             if (RuntimeEnabledFeatures::overlayFullscreenVideoEnabled()) {
                 Element* element = FullscreenElementStack::currentFullScreenElementFrom(*doc);
                 ASSERT(element);
-                if (isHTMLMediaElement(*element) && m_webViewImpl->layerTreeView())
-                    m_webViewImpl->layerTreeView()->setHasTransparentBackground(true);
+                if (isHTMLMediaElement(*element)) {
+                    HTMLMediaElement* mediaElement = toHTMLMediaElement(element);
+                    if (mediaElement->player() && mediaElement->player()->canShowFullscreenOverlay()
+                        // FIXME: There is no embedder-side handling in layout test mode.
+                        && !isRunningLayoutTest()) {
+                        mediaElement->player()->showFullscreenOverlay();
+                    }
+                    if (m_webViewImpl->layerTreeView())
+                        m_webViewImpl->layerTreeView()->setHasTransparentBackground(true);
+                }
             }
         }
     }
@@ -158,18 +166,6 @@ void FullscreenController::enterFullScreenForElement(WebCore::Element* element)
         return;
     }
 
-    if (RuntimeEnabledFeatures::overlayFullscreenVideoEnabled()
-        && isHTMLMediaElement(element)
-        // FIXME: There is no embedder-side handling in layout test mode.
-        && !isRunningLayoutTest()) {
-        HTMLMediaElement* mediaElement = toHTMLMediaElement(element);
-        if (mediaElement->player() && mediaElement->player()->canShowFullscreenOverlay()) {
-            mediaElement->player()->showFullscreenOverlay();
-            m_provisionalFullScreenElement = element;
-            return;
-        }
-    }
-
     // We need to transition to fullscreen mode.
     if (WebViewClient* client = m_webViewImpl->client()) {
         if (client->enterFullScreen())
@@ -182,15 +178,7 @@ void FullscreenController::exitFullScreenForElement(WebCore::Element* element)
     // The client is exiting full screen, so don't send a notification.
     if (m_isCancelingFullScreen)
         return;
-    if (RuntimeEnabledFeatures::overlayFullscreenVideoEnabled()
-        && isHTMLMediaElement(element)
-        // FIXME: There is no embedder-side handling in layout test mode.
-        && !isRunningLayoutTest()) {
-        HTMLMediaElement* mediaElement = toHTMLMediaElement(element);
-        if (mediaElement->player())
-            mediaElement->player()->hideFullscreenOverlay();
-        return;
-    }
+
     if (WebViewClient* client = m_webViewImpl->client())
         client->exitFullScreen();
 }