Actually call the NormlizeFilePath function for download platform detection.

This should make Cygwin work to match "win32".

Review URL: https://codereview.chromium.org/108743002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@239244 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed