Disable mozilla test that when timing out prints insane amounts of data.

I have filled a bug for this:
http://code.google.com/p/v8/issues/detail?id=960

Review URL: http://codereview.chromium.org/5662003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5930 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

test/mozilla/mozilla.status

@@ -53,6 +53,9 @@ def FAIL_OK = FAIL, OKAY
 # time to do so.
 js1_5/Regress/regress-271716-n: SKIP
 
+# BUG(960): This test has an insane amount of output when it times out,
+# messing up ability to see other failures on the waterfall.
+js1_5/extensions/regress-342960: SKIP
 
 # This test uses a unitialized variable. A Bug has been filed:
 # https://bugzilla.mozilla.org/show_bug.cgi?id=575575