Don't copy image buffer when calculating size.

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 a006e14ecf12ed5923416cedc75d9ba67eda782a..9ab9b8e0b1525f6a0167e01e58b8f9fe34e4a8c7 100644
--- a/src/image/SkImage_Gpu.cpp
+++ b/src/image/SkImage_Gpu.cpp
@@ -487,11 +487,7 @@ size_t SkImage::getDeferredTextureImageData(const GrContextThreadSafeProxy& prox
             ctSize = SkAlign8(pixmap.ctable()->count() * 4);
         }
     } else {
-        // Here we're just using presence of data to know whether there is a codec behind the image.
-        // In the future we will access the cacherator and get the exact data that we want to (e.g.
-        // yuv planes) upload.
-        sk_sp<SkData> data(this->refEncoded());
-        if (!data && !this->peekPixels(nullptr)) {
+        if (as_IB(this)->canGenerateTexture(proxy)) {
             return 0;
         }
         info = as_IB(this)->onImageInfo().makeWH(scaledSize.width(), scaledSize.height());