Fix JSBuiltinReducer to deal with non-JSFunction callees.

R=titzer@chromium.org
TEST=mozilla

Review URL: https://codereview.chromium.org/589573002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix TRACE_GENERIC_IC coverage

R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/585983002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24098 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Merge remote-tracking branch 'upstream/master'