There is an unused rowBytes parameter being passed along.

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 202 matching lines @@
             order to compensate for swizzling that will occur when drawing. */
         GrPixelConfig   fWriteConfig;
     };
 
     /**
      * Used to negotiate whether and how an intermediate surface should be used to write pixels to
      * a GrSurface. If this returns false then GrGpu could not deduce an intermediate draw
      * that would allow a successful transfer of the src pixels to the dst. The passed width,
      * height, and rowBytes, must be non-zero and already reflect clipping to the dst bounds.
      */
-    bool getWritePixelsInfo(GrSurface* dstSurface, int width, int height, size_t rowBytes,
+    bool getWritePixelsInfo(GrSurface* dstSurface, int width, int height,
                             GrPixelConfig srcConfig, DrawPreference*, WritePixelTempDrawInfo*);
 
     /**
      * Reads a rectangle of pixels from a render target.
      *
      * @param surface       The surface to read from
      * @param left          left edge of the rectangle to read (inclusive)
      * @param top           top edge of the rectangle to read (inclusive)
      * @param width         width of rectangle to read in pixels.
      * @param height        height of rectangle to read in pixels.
@@ skipping 291 matching lines @@
 
     // overridden by backend-specific derived class to perform the draw call.
     virtual void onDraw(const DrawArgs&, const GrNonInstancedVertices&) = 0;
 
     virtual bool onMakeCopyForTextureParams(GrTexture* texture, const GrTextureParams&,
                                             GrTextureProducer::CopyParams*) const { return false; }
 
     virtual bool onGetReadPixelsInfo(GrSurface* srcSurface, int readWidth, int readHeight,
                                      size_t rowBytes, GrPixelConfig readConfig, DrawPreference*,
                                      ReadPixelTempDrawInfo*) = 0;
-    virtual bool onGetWritePixelsInfo(GrSurface* dstSurface, int width, int height, size_t rowBytes,
+    virtual bool onGetWritePixelsInfo(GrSurface* dstSurface, int width, int height,
                                       GrPixelConfig srcConfig, DrawPreference*,
                                       WritePixelTempDrawInfo*) = 0;
 
     // overridden by backend-specific derived class to perform the surface read
     virtual bool onReadPixels(GrSurface*,
                               int left, int top,
                               int width, int height,
                               GrPixelConfig,
                               void* buffer,
                               size_t rowBytes) = 0;
@@ skipping 28 matching lines @@
     ResetTimestamp                                                      fResetTimestamp;
     uint32_t                                                            fResetBits;
     // The context owns us, not vice-versa, so this ptr is not ref'ed by Gpu.
     GrContext*                                                          fContext;
 
     friend class GrPathRendering;
     typedef SkRefCnt INHERITED;
 };
 
 #endif