Fix second memory leak in SkSpecialImage

src/core/SkSpecialImage.cpp

Index: src/core/SkSpecialImage.cpp
diff --git a/src/core/SkSpecialImage.cpp b/src/core/SkSpecialImage.cpp
index a5dc4b040be5030972bb5910e9c57f12b1bbcdfb..ecdd910c198379d418512ef03d28aa80a0a237a2 100644
--- a/src/core/SkSpecialImage.cpp
+++ b/src/core/SkSpecialImage.cpp
@@ -502,7 +502,8 @@ public:
         desc.fWidth = subset.width();
         desc.fHeight = subset.height();
 
-        GrTexture* subTx = ctx->textureProvider()->createTexture(desc, SkBudgeted::kYes);
+        SkAutoTUnref<GrTexture> subTx(ctx->textureProvider()->createTexture(desc,
+                                                                            SkBudgeted::kYes));
         if (!subTx) {
             return nullptr;
         }