Modify test using string slices
Modify test using string slices

With slices string string type removed generating a large amount of sub-strings takes more time. Change a test to avoid timeout in debug mode.
Review URL: http://codereview.chromium.org/385006

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@3260 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

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