Convert MediaMetricsProvider client to use BrowserInterfaceBroker

This CL converts MediaMetricsProvider mojom interface clients in
content to use BrowserInterfaceBroker.

Bug: 936482
Change-Id: I767ee109dcc6a01059e26736b1c739acad321d4e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1941464
Commit-Queue: Miyoung Shin <myid.shin@igalia.com>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Yuri Wiitala <miu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#720810}
6 files changed