Match cross-platform path separators.
Match cross-platform path separators.

TBR

Review URL: https://codereview.chromium.org//12310079

git-svn-id: b90127a0f73590c96be848d3e4cb640efa9a7657@18931 260f80e4-7a28-3924-810f-c04153c831b5

dart-archive/scheduled_test,dart-lang/scheduled_test