Version 3.20.7

Deprecated some debugger methods.

Fixed wrong bailout id in polymorphic stores (Chromium issue 259787).

Fixed data race in SamplingCircularQueue (Chromium issue 251218).

Fixed type feedback in presence of negative lookups (Chromium issue 252797).

Do not materialize context-allocated values for debug-evaluate (Chromium issue 259300).

Synchronized Compare-Literal behavior in FullCodegen and Hydrogen (Chromium issue 260345).

Performance and stability improvements on all platforms.

git-svn-id: https://v8.googlecode.com/svn/trunk@15795 ce2b1a6d-e550-0410-aec6-3dcde31c8c00