GitLab

To reuse all logic inside SharingMessageSender (metrics, timeouts and
acks) this introduces a SendMessageDelegate which is implemented once
for FCM and will be implemented for WebRTC in a future CL. This allows
us to dynamically choose the send implementation in the SharingService.

Bug: 1041032
Change-Id: Ib8abc2cf0c963a511ced12b71e09acde6fc0fa75
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1995332
Commit-Queue: Richard Knoll <knollr@chromium.org>
Reviewed-by: Himanshu Jaju <himanshujaju@chromium.org>
Cr-Commit-Position: refs/heads/master@{#731652}