Some Windows Command Prompt don't like if ... ( set PATH=... )

...it appears.  At least with Version 6.3.9600 on Windows 8.1, it results in
spurious

  \Windows was unexpected at this time.

past the first such construct.  Go figure.

Change-Id: I21cdb4edce0e7b22f26ac8b2f8b884f18490879b