Revert of some cleanup around GrGpu/GrDrawTarget copySurface

src/gpu/GrGpu.h

Index: src/gpu/GrGpu.h
diff --git a/src/gpu/GrGpu.h b/src/gpu/GrGpu.h
index d0bff30262c59a220af6dcea2ab25f87d89c1e52..b10a63f2dff2597bd81a4c623f77cbbdb205d72d 100644
--- a/src/gpu/GrGpu.h
+++ b/src/gpu/GrGpu.h
@@ -278,11 +278,10 @@
 
     /**
      * This is can be called before allocating a texture to be a dst for copySurface. It will
-     * populate the origin, config, and flags fields of the desc such that copySurface can
-     * efficiently succeed. It should only succeed if it can allow copySurface to perform a copy
-     * that would be more effecient than drawing the src to a dst render target.
-     */
-    virtual bool initCopySurfaceDstDesc(const GrSurface* src, GrSurfaceDesc* desc) = 0;
+     * populate the origin, config, and flags fields of the desc such that copySurface is more
+     * likely to succeed and be efficient.
+     */
+    virtual void initCopySurfaceDstDesc(const GrSurface* src, GrSurfaceDesc* desc);
 
     // After the client interacts directly with the 3D context state the GrGpu
     // must resync its internal state and assumptions about 3D context state.
@@ -338,20 +337,20 @@
     void saveActiveTraceMarkers();
     void restoreActiveTraceMarkers();
 
-    // 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.
+    // Called to determine whether an onCopySurface call would succeed or not. This is useful for
+    // proxy subclasses to test whether the copy would succeed without executing it yet. Derived
+    // 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(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.
+    // This method is called by copySurface  The srcRect is guaranteed to be entirely within the
+    // src bounds. Likewise, the dst rect implied by dstPoint and srcRect's width and height falls
+    // entirely within the dst. The default implementation will draw a rect from the src to the
+    // dst if the src is a texture and the dst is a render target and fail otherwise.
     virtual bool copySurface(GrSurface* dst,
                              GrSurface* src,
                              const SkIRect& srcRect,