Removed unused parameters

src/image/SkSurface_Gpu.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkSurface_Base.h"
 #include "SkImagePriv.h"
 #include "SkCanvas.h"
@@ skipping 68 matching lines @@
 }
 
 void SkSurface_Gpu::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y,
                               const SkPaint* paint) {
     canvas->drawBitmap(fDevice->accessBitmap(false), x, y, paint);
 }
 
 // Copy the contents of the SkGpuDevice into a new texture and give that
 // texture to the SkImage. Note that this flushes the SkGpuDevice but
 // doesn't force an OpenGL flush.
-void SkSurface_Gpu::onCopyOnWrite(SkImage* image, SkCanvas* canvas) {
+void SkSurface_Gpu::onCopyOnWrite(SkImage* image, SkCanvas*) {
     GrRenderTarget* rt = (GrRenderTarget*) fDevice->accessRenderTarget();
 
     // are we sharing our render target with the image?
     if (rt->asTexture() == SkTextureImageGetTexture(image)) {
         GrTextureDesc desc;
         // copyTexture requires a render target as the destination
         desc.fFlags = kRenderTarget_GrTextureFlagBit;
         desc.fWidth = fDevice->width();
         desc.fHeight = fDevice->height();
         desc.fConfig = SkBitmapConfig2GrPixelConfig(fDevice->config());
@@ skipping 37 matching lines @@
     desc.fConfig = SkBitmapConfig2GrPixelConfig(config);
     desc.fSampleCnt = sampleCount;
 
     SkAutoTUnref<GrTexture> tex(ctx->createUncachedTexture(desc, NULL, 0));
     if (NULL == tex) {
         return NULL;
     }
 
     return SkNEW_ARGS(SkSurface_Gpu, (ctx, tex->asRenderTarget()));
 }