Widen suppression for xhr test on mac in dartium to include drt

Review URL: https://codereview.chromium.org//718983002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@41683 260f80e4-7a28-3924-810f-c04153c831b5
diff --git a/tests/html/html.status b/tests/html/html.status
index 3d5f253..ecf5d31 100644
--- a/tests/html/html.status
+++ b/tests/html/html.status
@@ -356,7 +356,7 @@
 # Desktop operation systems do not support touch events on chrome 34 dartium.
 touchevent_test/supported: Fail
 
-[ ($runtime == dartium && $system == macos) || $system == windows ]
+[ (($runtime == dartium || $runtime == drt) && $system == macos) || $system == windows ]
 xhr_test/xhr: Skip # Times out.  Issue 21527
 
 [ $compiler == none && $runtime == dartium ]