Fix bug in prototype transitions cache clearing introduced by r8165.
Fix bug in prototype transitions cache clearing introduced by r8165.

Invalid loop nesting causes full cleanup of the prototype transitions cache on every GC.

R=ager@chromium.org

Review URL: http://codereview.chromium.org/7354020

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@8634 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh