Actually identify required saveLayers in SkGpuDevice::EXPERIMENTAL_drawPicture

src/core/SkCanvas.cpp

Index: src/core/SkCanvas.cpp
===================================================================
--- src/core/SkCanvas.cpp	(revision 13968)
+++ src/core/SkCanvas.cpp	(working copy)
@@ -2541,7 +2541,7 @@
     if (NULL != device) {
         // Canvas has to first give the device the opportunity to render
         // the picture itself.
-        if (device->EXPERIMENTAL_drawPicture(picture)) {
+        if (device->EXPERIMENTAL_drawPicture(&picture)) {
             return; // the device has rendered the entire picture
         }
     }