Alter SkCanvas::drawPicture (devirtualize, take const SkPicture, take pointer)

src/gpu/GrLayerCache.h

Index: src/gpu/GrLayerCache.h
diff --git a/src/gpu/GrLayerCache.h b/src/gpu/GrLayerCache.h
index 414b87dbb3d67c79d80c4f284d4b1c7ba808da24..a957e78013e05e3acabafac6821dfa4cc9cd46d5 100644
--- a/src/gpu/GrLayerCache.h
+++ b/src/gpu/GrLayerCache.h
@@ -102,7 +102,7 @@ public:
 
     void freeAll();
 
-    GrCachedLayer* findLayerOrCreate(SkPicture* picture, int id);
+    GrCachedLayer* findLayerOrCreate(const SkPicture* picture, int id);
 
 private:
     SkAutoTUnref<GrGpu>       fGpu;
@@ -113,7 +113,7 @@ private:
     GrTAllocPool<GrCachedLayer> fLayerPool;
 
     void init();
-    GrCachedLayer* createLayer(SkPicture* picture, int id);
+    GrCachedLayer* createLayer(const SkPicture* picture, int id);
 
 };