Bug 1381645 - Part 2: Move VR tests to secure context r=daoshengmu

MozReview-Commit-ID: CTDnXHBuaLU

--HG--
extra : rebase_source : a5be58d0cf10c2b4d7cbda95174793439af3fc5b

dom/vr/test/mochitest/mochitest.ini

@@ -1,5 +1,6 @@
 # Please confirm there is no other VR display connected. Otherwise, VRPuppetDisplay can't be attached.
 [DEFAULT]
+scheme = https
 support-files =
   VRSimulationDriver.js
   requestPresent.js