Add hittest mode for Touch-action which ignore inline elements and svg elements

Source/core/rendering/svg/RenderSVGRoot.cpp

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007, 2008, 2009 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 380 matching lines @@
     m_repaintBoundingBox.inflate(borderAndPaddingWidth());
 }
 
 bool RenderSVGRoot::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction hitTestAction)
 {
     LayoutPoint pointInParent = locationInContainer.point() - toLayoutSize(accumulatedOffset);
     LayoutPoint pointInBorderBox = pointInParent - toLayoutSize(location());
 
     // Only test SVG content if the point is in our content box.
     // FIXME: This should be an intersection when rect-based hit tests are supported by nodeAtFloatPoint.
-    if (contentBoxRect().contains(pointInBorderBox)) {
+    if (!request.touchAction() && contentBoxRect().contains(pointInBorderBox)) {

[Rick Byers, 2014/01/17 16:12:46]

RenderSVGRoot is a RenderBox so whatever we decide for RenderBox will probably
handle the SVG case.  The individual SVG elements are all RenderSVGModelObject
(not a RenderBox) so won't get touch-action hit testing applied to them if we
opt-in in RenderBox/RenderBlock.

[gnana, 2014/01/21 14:00:16]

commented reply below

         FloatPoint localPoint = localToParentTransform().inverse().mapPoint(FloatPoint(pointInParent));
 
         for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
             // FIXME: nodeAtFloatPoint() doesn't handle rect-based hit tests yet.
             if (child->nodeAtFloatPoint(request, result, localPoint, hitTestAction)) {
                 updateHitTestResult(result, pointInBorderBox);
                 if (!result.addNodeToRectBasedTestResult(child->node(), request, locationInContainer))
                     return true;
             }
         }
     }
 
     // If we didn't early exit above, we've just hit the container <svg> element. Unlike SVG 1.1, 2nd Edition allows container elements to be hit.
     if (hitTestAction == HitTestBlockBackground && visibleToHitTestRequest(request)) {

[gnana, 2014/01/21 14:00:16]

Yes, but visibleToHitTestRequest is called only for container <SVG>element. So
hit test will happen on the other svg elements before we reach here.

[Rick Byers, 2014/01/21 15:24:20]

Ah, I see!  Is there any good reason not to call visibleToHitTestRequest above
(in fact, I wonder if not doing so is responsible for some subtle bugs)? 
Regardless I think it's OK explicitly exclude touchAction above.

[leviw_travelin_and_unemployed, 2014/01/21 19:15:00]

This matches what we do in RenderBlock.

         // Only return true here, if the last hit testing phase 'BlockBackground' is executed. If we'd return true in the 'Foreground' phase,
         // hit testing would stop immediately. For SVG only trees this doesn't matter. Though when we have a <foreignObject> subtree we need
         // to be able to detect hits on the background of a <div> element. If we'd return true here in the 'Foreground' phase, we are not able
         // to detect these hits anymore.
         LayoutRect boundsRect(accumulatedOffset + location(), size());
         if (locationInContainer.intersects(boundsRect)) {
             updateHitTestResult(result, pointInBorderBox);
             if (!result.addNodeToRectBasedTestResult(node(), request, locationInContainer, boundsRect))
                 return true;
         }
@@ skipping 19 matching lines @@
 
 bool RenderSVGRoot::hasRelativeLogicalHeight() const
 {
     SVGSVGElement* svg = toSVGSVGElement(node());
     ASSERT(svg);
 
     return svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties).isPercent();
 }
 
 }