Change SkPicture::draw to playback

R=reed@google.com

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/540963002
diff --git a/tools/filtermain.cpp b/tools/filtermain.cpp
index a7ed20d..00854d4 100644
--- a/tools/filtermain.cpp
+++ b/tools/filtermain.cpp
@@ -679,7 +679,7 @@
 
     SkDebugCanvas debugCanvas(SkScalarCeilToInt(inPicture->cullRect().width()), 
                               SkScalarCeilToInt(inPicture->cullRect().height()));
-    inPicture->draw(&debugCanvas);
+    inPicture->playback(&debugCanvas);
 
     // delete the initial save and restore since replaying the commands will
     // re-add them