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

R=reed@google.com, bsalomon@google.com, mtklein@google.com

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/313613004
diff --git a/src/core/SkPictureShader.cpp b/src/core/SkPictureShader.cpp
index ecb86e7..81e1375 100644
--- a/src/core/SkPictureShader.cpp
+++ b/src/core/SkPictureShader.cpp
@@ -92,7 +92,7 @@
 
         SkCanvas canvas(bm);
         canvas.scale(tileScale.width(), tileScale.height());
-        canvas.drawPicture(*fPicture);
+        canvas.drawPicture(fPicture);
 
         fCachedTileScale = tileScale;
         fCachedLocalMatrix = this->getLocalMatrix();