Fix computation of clipped src rect when tiling bitmaps in SkGpuDevice

src/gpu/SkGpuDevice.cpp

Index: src/gpu/SkGpuDevice.cpp
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index 44d4354d45e0bef72414d7cbd924095c7ce7eb0c..864d124aead0603965c0f571351689180143d64a 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -686,8 +686,6 @@ static void determine_clipped_src_rect(int width, int height,
     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;