Simplify and speed up painting of clipping masks

third_party/WebKit/Source/core/paint/PaintLayerPainter.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PaintLayerPainter_h
 #define PaintLayerPainter_h
 
 #include "core/CoreExport.h"
 #include "core/paint/PaintLayerFragment.h"
 #include "core/paint/PaintLayerPaintingInfo.h"
 #include "core/paint/PaintResult.h"
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 class ClipRect;
 class PaintLayer;
 class GraphicsContext;
+class LayerClipRecorder;
 class LayoutPoint;
 
 // This class is responsible for painting self-painting PaintLayer.
 //
 // See PainterLayer SELF-PAINTING LAYER section about what 'self-painting'
 // means and how it impacts this class.
 class CORE_EXPORT PaintLayerPainter {
   STACK_ALLOCATED();
 
  public:
@@ skipping 84 matching lines @@
                                          PaintLayerFlags);
   void paintMaskForFragments(const PaintLayerFragments&,
                              GraphicsContext&,
                              const PaintLayerPaintingInfo&,
                              PaintLayerFlags);
   void paintChildClippingMaskForFragments(const PaintLayerFragments&,
                                           GraphicsContext&,
                                           const PaintLayerPaintingInfo&,
                                           PaintLayerFlags);
 
+  void fillMaskingFragment(GraphicsContext&, const LayerClipRecorder&);
+
   static bool needsToClip(const PaintLayerPaintingInfo& localPaintingInfo,
                           const ClipRect&);
 
   // Returns whether this layer should be painted during sofware painting (i.e.,
   // not via calls from CompositedLayerMapping to draw into composited layers).
   bool shouldPaintLayerInSoftwareMode(const GlobalPaintFlags,
                                       PaintLayerFlags paintFlags);
 
   // Returns true if the painted output of this PaintLayer and its children is
   // invisible and therefore can't impact painted output.
   bool paintedOutputInvisible(const PaintLayerPaintingInfo&);
 
   PaintLayer& m_paintLayer;
 
   FRIEND_TEST_ALL_PREFIXES(PaintLayerPainterTest, DontPaintWithTinyOpacity);
   FRIEND_TEST_ALL_PREFIXES(PaintLayerPainterTest,
                            DontPaintWithTinyOpacityAndBackdropFilter);
   FRIEND_TEST_ALL_PREFIXES(PaintLayerPainterTest,
                            DoPaintWithCompositedTinyOpacity);
   FRIEND_TEST_ALL_PREFIXES(PaintLayerPainterTest, DoPaintWithNonTinyOpacity);
 };
 
 }  // namespace blink
 
 #endif  // PaintLayerPainter_h