This CL is part of the Call-Level Adaptation Processing design doc:
https://docs.google.com/document/d/1ZyC26yOCknrrcYa839ZWLxD6o6Gig5A3lVTh4E41074/edit?usp=sharing
By pushing VideoAdaptationCounters updates on VideoSourceRestrictions
changes, alongside the Resource* that triggered the adaptation, we are
able to update |active_counts_| without an explicit dependency on the
VideoStreamAdapter. This allows a future CL to split up "processor"
logic from "video stream encoder resource and active counts" logic,
which will ultimately be necessary in order to do processing on a
"processing queue" and encoder and stats logic on the "encoder queue".
If the restrictions got cleared by an API call
(ResetVideoSourceRestrictions() or SetDegradationPreference()) we pass
null as the "reason_resource". This allows is to clear the
active_counts_, and the code that invokes
OnVideoSourceRestrictionsUpdated() does not have to be aware of
active_counts_ (needed to split the processor module in two).
Bug: webrtc:11172
Change-Id: Icab6d5121c0ebd27d2a00f1bffc8191f8f05f562
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/173000
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31103}