Adds a no-op emulation of TestSuite, to prevent error spam (or outright
failure under -strict mode) in dev mode tests that accidentally pick
the things up in their class path.

Review at http://gwt-code-reviews.appspot.com/1399803

Review by: fabbott@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@9933 8db76d5a-ed1c-0410-87a9-c151d255dfc7