Move some parts of onReadPixels up to GrGpu readPixels.

src/gpu/gl/GrGLGpu.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 GrGLGpu_DEFINED
 #define GrGLGpu_DEFINED
 
@@ skipping 124 matching lines @@
     void onClear(GrRenderTarget*, const SkIRect* rect, GrColor color,
                  bool canIgnoreRect) override;
 
     void onClearStencilClip(GrRenderTarget*, const SkIRect& rect, bool insideClip) override;
 
     bool onReadPixels(GrSurface*,
                       int left, int top,
                       int width, int height,
                       GrPixelConfig,
                       void* buffer,
-                      size_t rowBytes) override;
+                      size_t rowBytes,
+                      size_t tightRowBytes) override;
 
     bool onWritePixels(GrSurface*,
                        int left, int top, int width, int height,
                        GrPixelConfig config, const void* buffer,
                        size_t rowBytes) override;
 
     void onResolveRenderTarget(GrRenderTarget* target) override;
 
     void onDraw(const DrawArgs&, const GrNonInstancedVertices&) override;
 
@@ skipping 339 matching lines @@
 
     // we record what stencil format worked last time to hopefully exit early
     // from our loop that tries stencil formats and calls check fb status.
     int fLastSuccessfulStencilFmtIdx;
 
     typedef GrGpu INHERITED;
     friend class GrGLPathRendering; // For accessing setTextureUnit.
 };
 
 #endif