svg/animations/svglengthlist-animation-3.html is flakey on Mac

http://webkit.org/b/120387

Marking this as flakey.

* platform/mac/TestExpectations:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154716 268f45cc-cd09-0410-ab3c-d52691b4dbfc

LayoutTests/ChangeLog

+2013-08-27  Dean Jackson  <dino@apple.com>
+
+        svg/animations/svglengthlist-animation-3.html is flakey on Mac
+        http://webkit.org/b/120387
+
+        Marking this as flakey.
+
+        * platform/mac/TestExpectations:
+
 2013-08-27  Morten Stenshorne  <mstensho@opera.com>
         Improve multicol intrinsic width calculation

LayoutTests/platform/mac/TestExpectations

@@ -1296,3 +1296,5 @@ webkit.org/b/120085 [ Lion ] http/tests/inspector/resource-tree/resource-tree-do
 webkit.org/b/120087 [ Lion ] fast/forms/submit-to-url-fragment.html [ Pass Crash ]
 
 webkit.org/b/117962 [ Lion ] media/video-played-collapse.html [ Failure Pass ]
+
+webkit.org/b/120387 svg/animations/svglengthlist-animation-3.html [ Pass Failure ]