Ensure playing back a picture always balances saves and restores

src/core/SkPicturePlayback.cpp

Index: src/core/SkPicturePlayback.cpp
diff --git a/src/core/SkPicturePlayback.cpp b/src/core/SkPicturePlayback.cpp
index f2356bdeff58a606e07698e17e4ec7348900f2e4..97ca60169d50ada4c14110fc849c2cebe8747608 100644
--- a/src/core/SkPicturePlayback.cpp
+++ b/src/core/SkPicturePlayback.cpp
@@ -1321,6 +1321,8 @@ void SkPicturePlayback::draw(SkCanvas& canvas, SkDrawPictureCallback* callback)
         }
     }
 
+    canvas.restoreToCount(originalSaveCount);

[scroggo, 2014/05/16 18:20:53]

There are a couple of other places where we return from this function. In one of
them (if the callback aborts the drawing), we also restoreToCount, and in the
other (Android only; another version of aborting playback - as a side note, it
seems like that could be implemented in Android as a callback and we can
eliminate some code?) we do not. It seems like we should in both cases (as long
as the latter sticks around), we should do the restore.

I think it would make sense to use a SkAutoCanvasRestore(&canvas, false) early
on. That would make sure that we catch all exit cases (also that the restore
happens last).

[robertphillips, 2014/05/16 19:18:15]

Done.

+
 #ifdef SPEW_CLIP_SKIPPING
     {
         size_t size =  skipRect.fSize + skipRRect.fSize + skipPath.fSize + skipRegion.fSize +