Stack trace API: poison stack frames below the first strict mode frame.

Function and receiver objects are not accessible for poisoned frames.

R=rossberg@chromium.org
BUG=v8:2564

Review URL: https://chromiumcodereview.appspot.com/13150003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14085 ce2b1a6d-e550-0410-aec6-3dcde31c8c00