Misc minor WinRT fixes and cleanups Change-Id: Ibf041e74d81ef266791e6b6a3bb43bf504b035b3 Reviewed-on: https://chromium-review.googlesource.com/374040 Commit-Queue: Geoff Lang <geofflang@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>