Fixes issue 3569.  LongLib.shr gave incorrect results
when the shift amount was greater than 32.  This revision adds
two new test cases and modifies LongLib.shr to handle them.

Review by: fabbott


git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@5270 8db76d5a-ed1c-0410-87a9-c151d255dfc7