Enabled partial swap support for software compositing.

cc/software_renderer.h

 // Copyright 2012 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 CC_SOFTWARE_RENDERER_H_
 #define CC_SOFTWARE_RENDERER_H_
 
 #include "base/basictypes.h"
 #include "cc/cc_export.h"
 #include "cc/direct_renderer.h"
@@ skipping 37 matching lines @@
     virtual void drawQuad(DrawingFrame&, const DrawQuad*) OVERRIDE;
     virtual void beginDrawingFrame(DrawingFrame&) OVERRIDE;
     virtual void finishDrawingFrame(DrawingFrame&) OVERRIDE;
     virtual bool flippedFramebuffer() const OVERRIDE;
     virtual void ensureScissorTestEnabled() OVERRIDE;
     virtual void ensureScissorTestDisabled() OVERRIDE;
 
 private:
     SoftwareRenderer(RendererClient*, ResourceProvider*, SoftwareOutputDevice*);
 
+    void clearCanvas(SkColor color);
+    void setClipRect(const gfx::Rect& rect);
     bool isSoftwareResource(ResourceProvider::ResourceId) const;
 
     void drawDebugBorderQuad(const DrawingFrame&, const DebugBorderDrawQuad*);
     void drawSolidColorQuad(const DrawingFrame&, const SolidColorDrawQuad*);
     void drawTextureQuad(const DrawingFrame&, const TextureDrawQuad*);
     void drawTileQuad(const DrawingFrame&, const TileDrawQuad*);
     void drawRenderPassQuad(const DrawingFrame& frame, const RenderPassDrawQuad*);
     void drawUnsupportedQuad(const DrawingFrame&, const DrawQuad*);
 
     RendererCapabilities m_capabilities;
     bool m_visible;
+    bool m_isScissorEnabled;
+    gfx::Rect m_scissorRect;
 
     SoftwareOutputDevice* m_outputDevice;
     scoped_ptr<SkCanvas> m_skRootCanvas;
     SkCanvas* m_skCurrentCanvas;
     SkPaint m_skCurrentPaint;
     scoped_ptr<ResourceProvider::ScopedWriteLockSoftware> m_currentFramebufferLock;
 
     DISALLOW_COPY_AND_ASSIGN(SoftwareRenderer);
 };
 
 }
 
 #endif  // CC_SOFTWARE_RENDERER_H_