Avoid absoluteImageURL() creating data URLs for canvas by default.

Source/core/rendering/HitTestResult.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 88 matching lines @@
     void setIsFirstLetter(bool b) { m_isFirstLetter = b; }
     void setIsOverWidget(bool b) { m_isOverWidget = b; }
 
     bool isSelected() const;
     String spellingToolTip(TextDirection&) const;
     String title(TextDirection&) const;
     const AtomicString& altDisplayString() const;
     Image* image() const;
     IntRect imageRect() const;
     KURL absoluteImageURL() const;
+    // This variant of absoluteImageURL will also convert <canvas> elements
+    // to huge image data URLs (very expensive).
+    KURL absoluteImageURLIncludingCanvasDataURL() const;
     KURL absoluteMediaURL() const;
     KURL absoluteLinkURL() const;
     String textContent() const;
     bool isLiveLink() const;
     bool isMisspelled() const;
     bool isContentEditable() const;
 
     bool isOverLink() const;
     // Returns true if it is rect-based hit test and needs to continue until the rect is fully
     // enclosed by the boundaries of a node.
     bool addNodeToRectBasedTestResult(Node*, const HitTestRequest&, const HitTestLocation& pointInContainer, const LayoutRect& = LayoutRect());
     bool addNodeToRectBasedTestResult(Node*, const HitTestRequest&, const HitTestLocation& pointInContainer, const FloatRect&);
     void append(const HitTestResult&);
 
     // If m_rectBasedTestResult is 0 then set it to a new NodeSet. Return *m_rectBasedTestResult. Lazy allocation makes
     // sense because the NodeSet is seldom necessary, and it's somewhat expensive to allocate and initialize. This method does
     // the same thing as mutableRectBasedTestResult(), but here the return value is const.
     const NodeSet& rectBasedTestResult() const;
 
     // Collapse the rect-based test result into a single target at the specified location.
     void resolveRectBasedTest(Node* resolvedInnerNode, const LayoutPoint& resolvedPointInMainFrame);
 
     // FIXME: Remove this.
     Node* targetNode() const { return innerNode(); }
 
 private:
+    KURL absoluteImageURLInternal(bool allowCanvas) const;
     NodeSet& mutableRectBasedTestResult(); // See above.
     HTMLMediaElement* mediaElement() const;
 
     HitTestLocation m_hitTestLocation;
 
     RefPtrWillBeMember<Node> m_innerNode;
     RefPtrWillBeMember<Node> m_innerPossiblyPseudoNode;
     RefPtrWillBeMember<Node> m_innerNonSharedNode;
     // FIXME: Nothing changes this to a value different from m_hitTestLocation!
     LayoutPoint m_pointInInnerNodeFrame; // The hit-tested point in innerNode frame coordinates.
     LayoutPoint m_localPoint; // A point in the local coordinate space of m_innerNonSharedNode's renderer. Allows us to efficiently
                               // determine where inside the renderer we hit on subsequent operations.
     RefPtrWillBeMember<Element> m_innerURLElement;
     RefPtr<Scrollbar> m_scrollbar;
     bool m_isOverWidget; // Returns true if we are over a widget (and not in the border/padding area of a RenderWidget for example).
     bool m_isFirstLetter;
 
     mutable OwnPtrWillBeMember<NodeSet> m_rectBasedTestResult;
 };
 
 } // namespace blink
 
 #endif // HitTestResult_h