M58 cherry-pick: Re-enable code accidently disabled for testing

NOTREECHECKS=true
NOTRY=true
NOPRESUBMIT=true

Change-Id: I6d7b9aa7afe101d287e32340f6db88d7eed5e662
Reviewed-on: https://skia-review.googlesource.com/9143
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/core/SkSpecialImage.cpp b/src/core/SkSpecialImage.cpp
index c523ae8..db6ff0c 100644
--- a/src/core/SkSpecialImage.cpp
+++ b/src/core/SkSpecialImage.cpp
@@ -479,7 +479,7 @@
         if (subset) {
             // TODO: if this becomes a bottle neck we could base this logic on what the size
             // will be when it is finally instantiated - but that is more fraught.
-            if (//fSurfaceProxy->priv().isExact() &&
+            if (fTextureProxy->priv().isExact() &&
                 0 == subset->fLeft && 0 == subset->fTop &&
                 fTextureProxy->width() == subset->width() &&
                 fTextureProxy->height() == subset->height()) {