Truncate booleans to 0/1 in truncating t-to-i.

Thanks to weiliang.lin2@gmail.com for discovering the issue.

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/26824002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17166 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Ensure lower <= upper bound

R=jkummerow@chromium.org
BUG=

Review URL: https://codereview.chromium.org/26959004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17167 ce2b1a6d-e550-0410-aec6-3dcde31c8c00