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/tools/lua/lua_pictures.cpp b/tools/lua/lua_pictures.cpp
index c8b205d..f1c5ce9 100644
--- a/tools/lua/lua_pictures.cpp
+++ b/tools/lua/lua_pictures.cpp
@@ -158,7 +158,7 @@
                                                     L.get(), gAccumulateFunc));
 
                 call_canvas(L.get(), canvas.get(), path, gStartCanvasFunc);
-                canvas->drawPicture(*pic);
+                canvas->drawPicture(pic);
                 call_canvas(L.get(), canvas.get(), path, gEndCanvasFunc);
 
             } else {