RTCStatsCollector collecting stats on multiple threads.
Changes GetStatsReport to a callback-based function. Stats collection
is dispatched to three different stats collecting methods, being
invoked asynchronously on the signaling, worker and network threads.
The three resulting stats reports are merged into one before returned.
The only current stats being collected is on the signaling thread, but
a FakeRTCStatsCollector is able to test the multi-threaded and
stats-merging behaviors. Future CLs simply have to put their stats
collecting code in the appropriate ProducePartialResultsOnFooThread
method.
BUG=chromium:627816
Review-Url: https://codereview.webrtc.org/2270033004
Cr-Original-Commit-Position: refs/heads/master@{#14064}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: c82f2e1613e394f92c56d14c38b3f9069075039e
3 files changed
