Performance tests for iterators.

R=wingo@igalia.com

Review URL: https://codereview.chromium.org/641123003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24675 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Enable libstdc++ debug mode in debug builds.

See https://gcc.gnu.org/onlinedocs/libstdc++/manual/debug_mode.html for
details about the debug mode.

BUG=v8:3638
LOG=y
R=jochen@chromium.org

Review URL: https://codereview.chromium.org/648293007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24676 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Blacklist tests that are too slow with TurboFan in debug mode.

R=jochen@chromium.org

Review URL: https://codereview.chromium.org/660653008

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24677 ce2b1a6d-e550-0410-aec6-3dcde31c8c00