Port r14388 (6843e0c9), r14389 (331ea32d) and r14390 (c8528d1c)

BUG=

Review URL: https://codereview.chromium.org/14305011

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14399 ce2b1a6d-e550-0410-aec6-3dcde31c8c00