Move canvas->surface association to the device subclasses

include/core/SkBitmapDevice.h

 
 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkBitmapDevice_DEFINED
 #define SkBitmapDevice_DEFINED
@@ skipping 115 matching lines @@
     bool onReadPixels(const SkImageInfo&, void*, size_t, int x, int y) SK_OVERRIDE;
     bool onWritePixels(const SkImageInfo&, const void*, size_t, int, int) SK_OVERRIDE;
     void* onAccessPixels(SkImageInfo* info, size_t* rowBytes) SK_OVERRIDE;
 
     /** Called when this device is installed into a Canvas. Balanced by a call
         to unlockPixels() when the device is removed from a Canvas.
     */
     void lockPixels() SK_OVERRIDE;
     void unlockPixels() SK_OVERRIDE;
 
+
+    /** Creates a backend bitmap for a new bitmap device.
+     * returns true on success, with compatible bitmap in \target.
+     */
+    static bool CreateBackendBitmap(const SkImageInfo& origInfo, SkBitmap* target);
 private:
     friend class SkCanvas;
     friend struct DeviceCM; //for setMatrixClip
     friend class SkDraw;
     friend class SkDrawIter;
     friend class SkDeviceFilteredPaint;
     friend class SkDeviceImageFilterProxy;
 
     friend class SkSurface_Raster;
+    friend class SkRasterDevice;
 
     // used to change the backend's pixels (and possibly config/rowbytes)
     // but cannot change the width/height, so there should be no change to
     // any clip information.
-    void replaceBitmapBackendForRasterSurface(const SkBitmap&) SK_OVERRIDE;
+    void replaceBitmapBackend(const SkBitmap&) SK_OVERRIDE;
 
     SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
 
     SkSurface* newSurface(const SkImageInfo&, const SkSurfaceProps&) SK_OVERRIDE;
     const void* peekPixels(SkImageInfo*, size_t* rowBytes) SK_OVERRIDE;
 
     SkImageFilter::Cache* getImageFilterCache() SK_OVERRIDE;
 
     SkBitmap    fBitmap;
 
     typedef SkBaseDevice INHERITED;
 };
 
 #endif // SkBitmapDevice_DEFINED