Merged r16816 into trunk branch.

Reverted ("Chromium 284577 needs a mitigation CL added." (svn-id 16742)). Also changed a check in heap-inl.h for diagnosing 284577 into an assert.

R=mvstanton@chromium.org
BUG=

Review URL: https://codereview.chromium.org/24169006

git-svn-id: http://v8.googlecode.com/svn/trunk@16822 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
3 files changed