Force eager compilation of parenthesized functions.

Force eager compilation of parenthesized functions.

This makes the compiler use eager compilation for function literals that
are parenthesized. We consider this to be a hint that the function will
be called immediatly and hence try to avoid parsing it twice. The parser
already respects this heuristic.

R=ulan@chromium.org

Review URL: https://chromiumcodereview.appspot.com/10836132

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12270 ce2b1a6d-e550-0410-aec6-3dcde31c8c00