Avoid calling updateAllLifecyclePhasesExceptPaint in SVGImage if not needed.

third_party/WebKit/Source/core/frame/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. 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
@@ skipping 258 matching lines @@
 
     enum UrlFragmentBehavior {
         UrlFragmentScroll,
         UrlFragmentDontScroll
     };
     // Updates the fragment anchor element based on URL's fragment identifier.
     // Updates corresponding ':target' CSS pseudo class on the anchor element.
     // If |UrlFragmentScroll| is passed in then makes the anchor element
     // focused and also visible by scrolling to it. The scroll position is
     // maintained during the frame loading process.
-    void processUrlFragment(const KURL&, UrlFragmentBehavior = UrlFragmentScroll);
+    // Returns false if the URL behavior is unchanged from last time this method was called.

[fs, 2016/05/23 21:25:56]

Maybe also mention that false is returned if the fragment is not applied/no
scroll happens et.c?

+    bool processUrlFragment(const KURL&, UrlFragmentBehavior = UrlFragmentScroll);
     void clearFragmentAnchor();
 
     // Methods to convert points and rects between the coordinate space of the layoutObject, and this view.
     IntRect convertFromLayoutObject(const LayoutObject&, const IntRect&) const;
     IntRect convertToLayoutObject(const LayoutObject&, const IntRect&) const;
     IntPoint convertFromLayoutObject(const LayoutObject&, const IntPoint&) const;
     IntPoint convertToLayoutObject(const LayoutObject&, const IntPoint&) const;
 
     bool isFrameViewScrollCorner(LayoutScrollbarPart* scrollCorner) const { return m_scrollCorner == scrollCorner; }
 
@@ skipping 615 matching lines @@
     RefPtr<TransformPaintPropertyNode> m_preTranslation;
     RefPtr<TransformPaintPropertyNode> m_scrollTranslation;
     // The content clip clips the document (= LayoutView) but not the scrollbars.
     // TODO(trchen): This will not be needed once settings->rootLayerScrolls() is enabled.
     RefPtr<ClipPaintPropertyNode> m_contentClip;
 
     bool m_isUpdatingAllLifecyclePhases;
     ScrollAnchor m_scrollAnchor;
 
     bool m_needsScrollbarsUpdate;
+
+    KURL m_currentUrl;
+    UrlFragmentBehavior m_currentUrlFragmentBehavior;
 };
 
 inline void FrameView::incrementVisuallyNonEmptyCharacterCount(unsigned count)
 {
     if (m_isVisuallyNonEmpty)
         return;
     m_visuallyNonEmptyCharacterCount += count;
     // Use a threshold value to prevent very small amounts of visible content from triggering didMeaningfulLayout.
     // The first few hundred characters rarely contain the interesting content of the page.
     static const unsigned visualCharacterThreshold = 200;
@@ skipping 11 matching lines @@
     if (m_visuallyNonEmptyPixelCount > visualPixelThreshold)
         setIsVisuallyNonEmpty();
 }
 
 DEFINE_TYPE_CASTS(FrameView, Widget, widget, widget->isFrameView(), widget.isFrameView());
 DEFINE_TYPE_CASTS(FrameView, ScrollableArea, scrollableArea, scrollableArea->isFrameView(), scrollableArea.isFrameView());
 
 } // namespace blink
 
 #endif // FrameView_h