Drawstate on stack

src/gpu/GrGpu.h

Index: src/gpu/GrGpu.h
diff --git a/src/gpu/GrGpu.h b/src/gpu/GrGpu.h
index dfc71fe9709df5cd39c3d7c13c939c43a8e3b28b..5c25927418ac1d12d39c9f7de2d3f0012e92c0d5 100644
--- a/src/gpu/GrGpu.h
+++ b/src/gpu/GrGpu.h
@@ -360,8 +360,8 @@ public:
     // classes must keep this consistent with their implementation of onCopySurface(). The inputs
     // are the same as onCopySurface(), i.e. srcRect and dstPoint are clipped to be inside the src
     // and dst bounds.
-    virtual bool canCopySurface(GrSurface* dst,
-                                GrSurface* src,
+    virtual bool canCopySurface(const GrSurface* dst,
+                                const GrSurface* src,
                                 const SkIRect& srcRect,
                                 const SkIPoint& dstPoint) = 0;