Allow spaces in GN target names on Windows.
Allow spaces in GN target names on Windows.

This allows executables with spaces in their names to work on Windows. Posix probably needs a separate patch.

BUG=599326

Review URL: https://codereview.chromium.org/1846873002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#384445}

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