Expand tap highlight to allow multiple highlights for touch disambiguation.

Source/core/page/TouchDisambiguation.cpp

 /*
  * Copyright (C) 2012 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 70 matching lines @@
     score *= max((padding - abs(distance.height())) * reciprocalPadding, 0.f);
 
     return score;
 }
 
 struct TouchTargetData {
     IntRect windowBoundingBox;
     float score;
 };
 
-void findGoodTouchTargets(const IntRect& touchBox, Frame* mainFrame, Vector<IntRect>& goodTargets)
+void findGoodTouchTargets(const IntRect& touchBox, Frame* mainFrame, Vector<IntRect>& goodTargets, Vector<Node*>& highlightNodes)
 {
     goodTargets.clear();
 
     int touchPointPadding = ceil(max(touchBox.width(), touchBox.height()) * 0.5);
 
     IntPoint touchPoint = touchBox.center();
     IntPoint contentsPoint = mainFrame->view()->windowToContents(touchPoint);
 
     HitTestResult result = mainFrame->eventHandler()->hitTestResultAtPoint(contentsPoint, HitTestRequest::ReadOnly | HitTestRequest::Active | HitTestRequest::DisallowShadowContent, IntSize(touchPointPadding, touchPointPadding));
     const ListHashSet<RefPtr<Node> >& hitResults = result.rectBasedTestResult();
@@ skipping 35 matching lines @@
             }
         }
     }
 
     for (HashMap<Node*, TouchTargetData>::iterator it = touchTargets.begin(); it != touchTargets.end(); ++it) {
         // Currently the scoring function uses the overlap area with the fat point as the score.
         // We ignore the candidates that has less than 1/2 overlap (we consider not really ambiguous enough) than the best candidate to avoid excessive popups.
         if (it->value.score < bestScore * 0.5)
             continue;
         goodTargets.append(it->value.windowBoundingBox);
+        highlightNodes.append(it->key);
     }
 }
 
 } // namespace WebCore