Bug 1237146 - Enable this now-passing test. r=billm

docshell/test/mochitest.ini

@@ -54,7 +54,7 @@ skip-if = true
 [test_bug509055.html]
 skip-if = (buildapp == 'b2g' && toolkit != 'gonk') #Bug 931116, b2g desktop specific, initial triage
 [test_bug511449.html]
-skip-if = toolkit != "cocoa" || e10s
+skip-if = toolkit != "cocoa"
 support-files = file_bug511449.html
 [test_bug529119-1.html]
 skip-if = buildapp == 'mulet' || (buildapp == 'b2g' && toolkit != 'gonk') #Bug 931116, b2g desktop specific, initial triage