Skip _CheckFilePermissions check on Windows

Executable bits are wonky on Windows, so checking them doesn't get us anything
and incorrectly disallows uploading of, e.g., python scripts.

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NOTRY=true

Review URL: https://codereview.chromium.org/142973008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248605 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed