Version 3.25.0 (based on bleeding_edge revision r19483)

ES6: Tighten up Object.prototype.__proto__ (issue 3064).

Fix Hydrogen bounds check elimination (Chromium issue 344186).

Performance and stability improvements on all platforms.

git-svn-id: https://v8.googlecode.com/svn/trunk@19484 ce2b1a6d-e550-0410-aec6-3dcde31c8c00