Revert 235626 "Remove blacklisting of Mac OS 10.6 and 10.7."

trunk/src/content/browser/gpu/compositor_util_browsertest.cc

Index: trunk/src/content/browser/gpu/compositor_util_browsertest.cc
===================================================================
--- trunk/src/content/browser/gpu/compositor_util_browsertest.cc	(revision 235643)
+++ trunk/src/content/browser/gpu/compositor_util_browsertest.cc	(working copy)
@@ -29,13 +29,8 @@
 #elif defined(OS_ANDROID)
   expected_mode = THREADED;
 #elif defined(OS_MACOSX)
-  expected_mode = THREADED;
-  // Lion has compositing blacklisted when using the Apple software renderer,
-  // so results will vary depending if this test is being run in a VM versus
-  // actual hardware.
-  // http://crbug.com/230931
-  if (base::mac::IsOSLion())
-    return;
+  if (base::mac::IsOSMountainLionOrLater())
+    expected_mode = THREADED;
 #elif defined(OS_WIN)
   if (base::win::GetVersion() >= base::win::VERSION_VISTA)
     expected_mode = THREADED;