Fix computation of clipped src rect when tiling bitmaps in SkGpuDevice

src/gpu/SkGpuDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGpuDevice.h"
 
 #include "GrBlurUtils.h"
@@ skipping 668 matching lines @@
                                        SkIRect* clippedSrcIRect) {
     clip.getConservativeBounds(width, height, clippedSrcIRect, nullptr);
     SkMatrix inv = SkMatrix::Concat(viewMatrix, srcToDstRect);
     if (!inv.invert(&inv)) {
         clippedSrcIRect->setEmpty();
         return;
     }
     SkRect clippedSrcRect = SkRect::Make(*clippedSrcIRect);
     inv.mapRect(&clippedSrcRect);
     if (srcRectPtr) {
-        // we've setup src space 0,0 to map to the top left of the src rect.
-        clippedSrcRect.offset(srcRectPtr->fLeft, srcRectPtr->fTop);
         if (!clippedSrcRect.intersect(*srcRectPtr)) {
             clippedSrcIRect->setEmpty();
             return;
         }
     }
     clippedSrcRect.roundOut(clippedSrcIRect);
     SkIRect bmpBounds = SkIRect::MakeSize(imageSize);
     if (!clippedSrcIRect->intersect(bmpBounds)) {
         clippedSrcIRect->setEmpty();
     }
@@ skipping 1020 matching lines @@
 }
 
 SkImageFilterCache* SkGpuDevice::getImageFilterCache() {
     ASSERT_SINGLE_OWNER
     // We always return a transient cache, so it is freed after each
     // filter traversal.
     return SkImageFilterCache::Create(kDefaultImageFilterCacheSize);
 }
 
 #endif