Move union length computation out of loops.

R=rossberg@chromium.org
BUG=

Review URL: https://codereview.chromium.org/600713003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24206 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Make type fuzzer return non-standard bitsets too.
(Also speed up some types tests a little.)

R=rossberg@chromium.org
BUG=

Review URL: https://codereview.chromium.org/602553002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24207 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix argument check in RandomNumberGenerator::NextInt.

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/597993002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24208 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Give more precise types to some Math functions.

R=rossberg@chromium.org
BUG=

Review URL: https://codereview.chromium.org/602693002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24209 ce2b1a6d-e550-0410-aec6-3dcde31c8c00