Version 3.28.0 (based on bleeding_edge revision r21907)

MIPS: Support LiveEdit (Chromium issue 368580).

Array.concat: properly go to dictionary mode when required (Chromium issue 387031).

Support LiveEdit on ARM (Chromium issue 368580).

Performance and stability improvements on all platforms.

git-svn-id: https://v8.googlecode.com/svn/trunk@21910 ce2b1a6d-e550-0410-aec6-3dcde31c8c00