Revert of Move copy-surface-as-draw fallback to GrGLGpu.

src/gpu/GrGpu.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGpu_DEFINED
 #define GrGpu_DEFINED
 
@@ skipping 239 matching lines @@
     // Returns a timestamp based on the number of times the context was reset.
     // This timestamp can be used to lazily detect when cached 3D context state
     // is dirty.
     ResetTimestamp getResetTimestamp() const { return fResetTimestamp; }
 
     virtual void buildProgramDesc(GrProgramDesc*,
                                   const GrPrimitiveProcessor&,
                                   const GrPipeline&,
                                   const GrBatchTracker&) const = 0;
 
+    // Called to determine whether a copySurface call would succeed or not. Derived
+    // classes must keep this consistent with their implementation of onCopySurface(). Fallbacks
+    // to issuing a draw from the src to dst take place at the GrDrawTarget level and this function
+    // should only return true if a faster copy path exists. The rect and point are pre-clipped. The
+    // src rect and implied dst rect are guaranteed to be within the src/dst bounds and non-empty.
+    virtual bool canCopySurface(const GrSurface* dst,
+                                const GrSurface* src,
+                                const SkIRect& srcRect,
+                                const SkIPoint& dstPoint) = 0;
+
     // Called to perform a surface to surface copy. Fallbacks to issuing a draw from the src to dst
     // take place at the GrDrawTarget level and this function implement faster copy paths. The rect
     // and point are pre-clipped. The src rect and implied dst rect are guaranteed to be within the
     // src/dst bounds and non-empty.
     virtual bool copySurface(GrSurface* dst,
                              GrSurface* src,
                              const SkIRect& srcRect,
                              const SkIPoint& dstPoint) = 0;
 
     // Called before certain draws in order to guarantee coherent results from dst reads.
@@ skipping 215 matching lines @@
     int                                                                 fGpuTraceMarkerCount;
     GrTraceMarkerSet                                                    fActiveTraceMarkers;
     GrTraceMarkerSet                                                    fStoredTraceMarkers;
     // The context owns us, not vice-versa, so this ptr is not ref'ed by Gpu.
     GrContext*                                                          fContext;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif