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

src/effects/SkXfermodeImageFilter.cpp

Index: src/effects/SkXfermodeImageFilter.cpp
diff --git a/src/effects/SkXfermodeImageFilter.cpp b/src/effects/SkXfermodeImageFilter.cpp
index a7f50c30cd08d0f17c7aba56ec70b707c4f5c9b7..c26ca18041ffb9315e955a96a089ee996d34f2fd 100644
--- a/src/effects/SkXfermodeImageFilter.cpp
+++ b/src/effects/SkXfermodeImageFilter.cpp
@@ -70,12 +70,12 @@ bool SkXfermodeImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, Sk
     if (!SkImageFilterUtils::GetInputResultGPU(getInput(0), proxy, src, &background)) {
         return false;
     }
-    GrTexture* backgroundTex = (GrTexture*) background.getTexture();
+    GrTexture* backgroundTex = background.getTexture();
     SkBitmap foreground;
     if (!SkImageFilterUtils::GetInputResultGPU(getInput(1), proxy, src, &foreground)) {
         return false;
     }
-    GrTexture* foregroundTex = (GrTexture*) foreground.getTexture();
+    GrTexture* foregroundTex = foreground.getTexture();
     GrContext* context = foregroundTex->getContext();
 
     GrEffectRef* xferEffect = NULL;