Change expectations for DebuggerAgent test.

Review URL: http://codereview.chromium.org/42444

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1561 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

test/cctest/cctest.status

@@ -30,6 +30,9 @@ prefix cctest
 # BUG(96): Fix this flaky test.
 test-debug/ThreadedDebugging: PASS || FAIL
 
+# BUG(281): This test fails on some Linuxes.
+test-debug/DebuggerAgent: PASS, (PASS || FAIL) if $system == linux
+
 [ $arch == arm ]
 
 test-debug: SKIP