Report correct touch hit rects for fullscreen HTML5 video on Android

Source/core/page/scrolling/ScrollingCoordinator.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 760 matching lines @@
 
     const FrameTree& tree = frame->tree();
     for (Frame* subFrame = tree.firstChild(); subFrame; subFrame = subFrame->tree().nextSibling()) {
         if (subFrame->isLocalFrame())
             shouldHandleScrollGestureOnMainThreadRegion.unite(computeShouldHandleScrollGestureOnMainThreadRegion(toLocalFrame(subFrame), offset));
     }
 
     return shouldHandleScrollGestureOnMainThreadRegion;
 }
 
-static void accumulateDocumentTouchEventTargetRects(LayerHitTestRects& rects, const Document* document)
+static void accumulateDocumentTouchEventTargetRects(LayerHitTestRects& rects, Document* document)
 {
     ASSERT(document);
     if (!document->touchEventTargets())
         return;
 
     const TouchEventTargetSet* targets = document->touchEventTargets();
 
     // If there's a handler on the document, html or body element (fairly common in practice),
     // then we can quickly mark the entire document and skip looking at any other handlers.
     // Note that technically a handler on the body doesn't cover the whole document, but it's
     // reasonable to be conservative and report the whole document anyway.
-    for (TouchEventTargetSet::const_iterator iter = targets->begin(); iter != targets->end(); ++iter) {
+    //
+    // Fullscreen HTML5 video on Android is implemented by replacing the root cc:layer with the
+    // video layer so doing this optimization causes the compositor to think that there are no
+    // handlers when in full screen therefore skip it.
+    bool inFullscreenOnAndroid = RuntimeEnabledFeatures::overlayFullscreenVideoEnabled() && RenderLayerCompositor::findFullscreenVideoRenderer(*document);

[abarth-chromium, 2014/06/07 09:06:03]

It's inefficient to call findFullscreenVideoRenderer more than once per frame. 
Can the RenderLayerCompositor and this code share the information about whether
we're inFullscreenOnAndroid instead of each computing it separately.

Also, please don't refer to Android in the variable name.  In principle, this
can happen whenever RuntimeEnabledFeatures::overlayFullscreenVideoEnabled is
true, regardless of whether we're on Android.

+    for (TouchEventTargetSet::const_iterator iter = targets->begin(); !inFullscreenOnAndroid && iter != targets->end(); ++iter) {
         Node* target = iter->key;
         if (target == document || target == document->documentElement() || target == document->body()) {
             if (RenderView* rendererView = document->renderView()) {
                 rendererView->computeLayerHitTestRects(rects);
             }
             return;
         }
     }
 
     for (TouchEventTargetSet::const_iterator iter = targets->begin(); iter != targets->end(); ++iter) {
-        const Node* target = iter->key;
+        Node* target = iter->key;
         if (!target->inDocument())
             continue;
 
-        if (target->isDocumentNode()) {
-            ASSERT(target != document);
+        if (target->isDocumentNode() && target != document) {
             accumulateDocumentTouchEventTargetRects(rects, toDocument(target));
         } else if (RenderObject* renderer = target->renderer()) {
             // If the set also contains one of our ancestor nodes then processing
             // this node would be redundant.
             bool hasTouchEventTargetAncestor = false;
             for (Node* ancestor = target->parentNode(); ancestor && !hasTouchEventTargetAncestor; ancestor = ancestor->parentNode()) {
                 if (targets->contains(ancestor))
                     hasTouchEventTargetAncestor = true;
             }
             if (!hasTouchEventTargetAncestor) {
@@ skipping 157 matching lines @@
     bool frameIsScrollable = frameView && frameView->isScrollable();
     if (frameIsScrollable != m_wasFrameScrollable)
         return true;
 
     if (WebLayer* scrollLayer = frameView ? toWebLayer(frameView->layerForScrolling()) : 0)
         return blink::WebSize(frameView->contentsSize()) != scrollLayer->bounds();
     return false;
 }
 
 } // namespace WebCore