Bug 838942 - DMD: Fix assertion in the test on Windows.  r=jlebar.  DONTBUILD because DMD isn't built by default.

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extra : rebase_source : e2075b1b34bbfc7d0a3b9f45523323a7f38dcb63
Bug 839134 - ADB doesn't get enabled in VARIANT=user builds if marionette pref doesn't exist.