Fix function name inferring inside closures

BUG=224884
R=loislo@chromium.org, yangguo@chromium.org

Review URL: https://codereview.chromium.org/16125007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14903 ce2b1a6d-e550-0410-aec6-3dcde31c8c00