Extra IC state is only two bits and only supported for call IC-s for
now. To change its extra state an IC stub jumps to a new miss stub
that goes to runtime as usual but then instead of going megamorphic
generates a monomorphic stub with the updated state.

Review URL: http://codereview.chromium.org/6344005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6370 ce2b1a6d-e550-0410-aec6-3dcde31c8c00