This change creates the new export CreateVRWindow from vrhost.dll. This API
results in spawning a new Firefox window with the Firefox Reality 2D UI and
returns data needed for the host to interact with it. VRShMem is used to pass
data across process boundaries during this bootstrap process.
Additional tests are added to vrhost to be later converted to unittests.
Differential Revision: https://phabricator.services.mozilla.com/D40236
--HG--
rename : gfx/vr/vrhost/vrhost.cpp => gfx/vr/vrhost/vrhosttest.cpp
extra : moz-landing-system : lando
94cc4efcb3