Change SkPicture::draw to playback

include/core/SkPicture.h

Index: include/core/SkPicture.h
diff --git a/include/core/SkPicture.h b/include/core/SkPicture.h
index 7f0665e046d86cb070b33210a3f3fcd5572d72ed..d8aced19ab21cf59b22dbb09d6c8a63b5185e847 100644
--- a/include/core/SkPicture.h
+++ b/include/core/SkPicture.h
@@ -111,10 +111,20 @@ public:
     SkPicture* clone() const;
 #endif
 
-    /** Replays the drawing commands on the specified canvas.
+    /** Replays the drawing commands on the specified canvas. Note that
+        this has the effect of unfurling this picture into the destination
+        canvas. Using the SkCanvas::drawPicture entry point gives the destination
+        canvas the option of just taking a ref.
         @param canvas the canvas receiving the drawing commands.
+        @param callback a callback that allows interruption of playback
     */
-    void draw(SkCanvas* canvas, SkDrawPictureCallback* = NULL) const;
+    void playback(SkCanvas* canvas, SkDrawPictureCallback* = NULL) const;
+
+#ifdef SK_LEGACY_PICTURE_DRAW_API
+    void draw(SkCanvas* canvas, SkDrawPictureCallback* callback = NULL) const {
+        this->playback(canvas, callback);
+    }
+#endif
 
 #ifdef SK_LEGACY_PICTURE_SIZE_API
     int width() const  { return SkScalarCeilToInt(fCullWidth); }