Convert XRSessionController to new Mojo types

This CL converts XRSessionController{Ptr, Request} in chrome and
device to the new Mojo type, and use
pending_remote<XRSessionController> in isolated_xr_service.mojom.

This CL also remove unnecessary InterfaceSet and it is replaced
with RemoteSet.

Bug: 955171, 965668
Change-Id: I388f1be9010b6c91a0f1fa00bfc719accd457f66
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1846418
Commit-Queue: Miyoung Shin <myid.shin@igalia.com>
Reviewed-by: Sam McNally <sammc@chromium.org>
Reviewed-by: Klaus Weidner <klausw@chromium.org>
Reviewed-by: Piotr Bialecki <bialpio@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#704562}
28 files changed