content: Enable impl-side painting on Windows.

BUG=169282

Review URL: https://codereview.chromium.org/392623003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@283229 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/browser/gpu/compositor_util.cc b/content/browser/gpu/compositor_util.cc
index bcc6a9e..7290430 100644
--- a/content/browser/gpu/compositor_util.cc
+++ b/content/browser/gpu/compositor_util.cc
@@ -230,7 +230,7 @@
       switches::kEnableBleedingEdgeRenderingFastPaths))
     return true;
 
-#if defined(OS_MACOSX) || defined(OS_WIN)
+#if defined(OS_MACOSX)
   return false;
 #else
   return IsThreadedCompositingEnabled();