Fixes Starfield not being able to take photos in photo mode (due to failing to creating windowscodecs' image factory due to COM apartment being initialized). Turns out on Windows RoGetActivationFactory() initializes implicit MTA apartment when called from STA thread, and so after that called once COM is implicitly uninitialized for any (new) thread until COM is uninitialized in the thread which called RoGetActivationFactory (or that thread exited). This is not the case on Win8 (where the function was first introduced) but looks consistent after that.
-- v2: combase: Create implicit MTA in STA apartment in RoGetActivationFactory().