Use SkImageCacherator in SkImages

src/image/SkImage_Gpu.cpp

Index: src/image/SkImage_Gpu.cpp
diff --git a/src/image/SkImage_Gpu.cpp b/src/image/SkImage_Gpu.cpp
index fdcb87136db528f79b666ff8e39ac0ee6dbcba9a..163e62e02df540362952e9b55be47d3284d886a7 100644
--- a/src/image/SkImage_Gpu.cpp
+++ b/src/image/SkImage_Gpu.cpp
@@ -79,6 +79,11 @@ bool SkImage_Gpu::getROPixels(SkBitmap* dst) const {
     return true;
 }
 
+GrTexture* SkImage_Gpu::asTextureRef(GrContext* ctx, SkImageUsageType usage) const {
+    fTexture->ref();
+    return fTexture;
+}
+
 bool SkImage_Gpu::isOpaque() const {
     return GrPixelConfigIsOpaque(fTexture->config()) || fAlphaType == kOpaque_SkAlphaType;
 }