Image filters: fix srcOffset handling in asFragmentProcessor() path.

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index 141d2e03fbea36eaf89c74dda95aa12b18d25ea6..821edc0e1abbd6af85e2b9f41a6e28a5a27ef4de 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -334,8 +334,6 @@ bool SkImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Cont
     if (!this->applyCropRect(ctx, proxy, input, &srcOffset, &bounds, &input)) {
         return false;
     }
-    SkRect srcRect = SkRect::Make(bounds);
-    SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
     GrContext* context = srcTexture->getContext();
 
     GrSurfaceDesc desc;
@@ -349,9 +347,6 @@ bool SkImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Cont
         return false;
     }
 
-    // setup new clip
-    GrClip clip(dstRect);
-
     GrFragmentProcessor* fp;
     offset->fX = bounds.left();
     offset->fY = bounds.top();
@@ -366,6 +361,9 @@ bool SkImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Cont
 
         SkAutoTUnref<GrDrawContext> drawContext(context->drawContext(dst->asRenderTarget()));
         if (drawContext) {
+            SkRect srcRect = SkRect::Make(bounds);
+            SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
+            GrClip clip(dstRect);
             drawContext->fillRectToRect(clip, paint, SkMatrix::I(), dstRect, srcRect);
 
             GrWrapTextureInBitmap(dst, bounds.width(), bounds.height(), false, result);