Fix GC issue in instanceof stub

Fix GC issue in instanceof stub

The the call of the builtin in InstanceofStub was not correctly protected with an internal frame leading to the return address being handled as a pointer during GC.

Marked the Instanceof stub as allowing stub calls (the RecordWriteStub was removed some days ago).

This issue was not caught by the assertion designed for this when debug mode is run with --debug-code (which out tests always does) as generating code for Abort set the allow stub calls flag to true. This has been fixed by restoring the allow stub calls flag correctly.
Review URL: http://codereview.chromium.org/6097010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6218 ce2b1a6d-e550-0410-aec6-3dcde31c8c00