http/tests/navigation/anchor-basic.html is flaky on Snow Leopard Release Bot

http/tests/navigation/anchor-basic.html is flaky on Snow Leopard Release Bot
https://bugs.webkit.org/show_bug.cgi?id=34222

Reviewed by Ryosuke Niwa.

Add waitUntilDone/notifyDone to eliminate flakiness on mac. Without it, the img onload handler
doesn't always run. Also reduce the multipart timeout (should help to unblock other http requests).

* http/tests/multipart/stop-crash-expected.txt:
* http/tests/multipart/stop-crash.html:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@96174 268f45cc-cd09-0410-ab3c-d52691b4dbfc