Revert "Revert "SkImageInfoValidConversion (part 2)""

This reverts commit 8dadd9e8936a1c8f44fccdfde7f883dfe2d89c96.

Reason for revert: Fixed Chrome.  This should roll now.

Original change's description:
> Revert "SkImageInfoValidConversion (part 2)"
> 
> This reverts commit 94bd50cc5575b90eb60234399d69905b8651c27e.
> 
> Reason for revert: Still breaking roll
> 
> Original change's description:
> > SkImageInfoValidConversion (part 2)
> > 
> > Disabling non-opaque -> opaque should be fine now that the
> > Chrome unit test has been fixed.
> > 
> > BUG=skia:6021
> > 
> > Change-Id: I39f087e2695bdefacf793bd137931e3115ec58cb
> > Reviewed-on: https://skia-review.googlesource.com/7121
> > Reviewed-by: Brian Osman <brianosman@google.com>
> > Commit-Queue: Matt Sarett <msarett@google.com>
> > 
> 
> TBR=msarett@google.com,brianosman@google.com
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=skia:6021
> 
> Change-Id: I79843ea6cf60ca94822446c548f3386706924ee6
> Reviewed-on: https://skia-review.googlesource.com/7164
> Commit-Queue: Matt Sarett <msarett@google.com>
> Reviewed-by: Matt Sarett <msarett@google.com>
> 

TBR=msarett@google.com,brianosman@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:6021

Change-Id: I40a85ac2e407de15916f0893d55163aea44157cb
Reviewed-on: https://skia-review.googlesource.com/7181
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Matt Sarett <msarett@google.com>
diff --git a/src/core/SkImageInfoPriv.h b/src/core/SkImageInfoPriv.h
index 029aa93..72138ae 100644
--- a/src/core/SkImageInfoPriv.h
+++ b/src/core/SkImageInfoPriv.h
@@ -69,11 +69,9 @@
         return false;
     }
 
-    // FIXME (msarett): This is commented out until a fix to Chrome's gfx_unittest lands.
-    // In those tests, they write kPremul pixels to a kOpaque canvas.
-    //if (kOpaque_SkAlphaType == dst.alphaType() && kOpaque_SkAlphaType != src.alphaType()) {
-    //    return false;
-    //}
+    if (kOpaque_SkAlphaType == dst.alphaType() && kOpaque_SkAlphaType != src.alphaType()) {
+        return false;
+    }
 
     return true;
 }