use SkPixmap inside sprite blitters

src/core/SkSpriteBlitter.h

Index: src/core/SkSpriteBlitter.h
diff --git a/src/core/SkSpriteBlitter.h b/src/core/SkSpriteBlitter.h
index f69a55a2a0bfdc79f483ce6a821beec0c1794d1b..0bbc8561d0d441c9050fb7addc57d1862304fef9 100644
--- a/src/core/SkSpriteBlitter.h
+++ b/src/core/SkSpriteBlitter.h
@@ -20,11 +20,9 @@ class SkPaint;
 
 class SkSpriteBlitter : public SkBlitter {
 public:
-            SkSpriteBlitter(const SkBitmap& source);
-    virtual ~SkSpriteBlitter();
+    SkSpriteBlitter(const SkBitmap& source);
 
-    virtual void setup(const SkBitmap& device, int left, int top,
-                       const SkPaint& paint);
+    virtual bool setup(const SkBitmap& device, int left, int top, const SkPaint& paint);
 
     // overrides
 #ifdef SK_DEBUG
@@ -41,9 +39,12 @@ public:
 
 protected:
     const SkBitmap* fDevice;
-    const SkBitmap* fSource;
+    const SkPixmap* fSource;
     int             fLeft, fTop;
     const SkPaint*  fPaint;
+
+private:
+    SkAutoPixmapUnlock fUnlocker;
 };
 
 #endif