Reland: Add mock_rtc_event_log.h.

Bug: webrtc:7642
Change-Id: I3f97a8b603e34819e1563b335c1eeb51f89b11ac
Reviewed-on: https://webrtc-review.googlesource.com/37081
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Patrik Höglund <phoglund@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21480}
diff --git a/modules/remote_bitrate_estimator/BUILD.gn b/modules/remote_bitrate_estimator/BUILD.gn
index a5dd014..ef7ee11 100644
--- a/modules/remote_bitrate_estimator/BUILD.gn
+++ b/modules/remote_bitrate_estimator/BUILD.gn
@@ -143,6 +143,7 @@
       "../..:webrtc_common",
       "../../:typedefs",
       "../../api:optional",
+      "../../logging:mocks",
       "../../rtc_base:checks",
       "../../rtc_base:gtest_prod",
       "../../rtc_base:rtc_base",