Change undefined SkGpuRenderTarget and SkGpuTexture forward declares to GrRenderTarget and GrTextur…

src/effects/SkBlendImageFilter.cpp

Index: src/effects/SkBlendImageFilter.cpp
diff --git a/src/effects/SkBlendImageFilter.cpp b/src/effects/SkBlendImageFilter.cpp
index 330e87d76d8e8410477bf6b136a552a5422c4bfd..4f61ed80002acdb0d2ff82b65bec0c25ccc120ae 100644
--- a/src/effects/SkBlendImageFilter.cpp
+++ b/src/effects/SkBlendImageFilter.cpp
@@ -155,12 +155,12 @@ bool SkBlendImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, SkBit
     if (!SkImageFilterUtils::GetInputResultGPU(getBackgroundInput(), proxy, src, &backgroundBM)) {
         return false;
     }
-    GrTexture* background = (GrTexture*) backgroundBM.getTexture();
+    GrTexture* background = backgroundBM.getTexture();
     SkBitmap foregroundBM;
     if (!SkImageFilterUtils::GetInputResultGPU(getForegroundInput(), proxy, src, &foregroundBM)) {
         return false;
     }
-    GrTexture* foreground = (GrTexture*) foregroundBM.getTexture();
+    GrTexture* foreground = foregroundBM.getTexture();
     GrContext* context = foreground->getContext();
 
     GrTextureDesc desc;