This code was previously only exercised by
video_stream_adapter_unittest.cc and other tests, acting more like
integration tests than unit tests. Now that the VideoStreamAdapter is
in a good state, more extensive test coverage is added.
Testing includes:
- Default restrictions.
- Adapting up or down in "maintain-framerate", "maintain-resolution"
and "balanced", including...
- expecting how frame rate and/or resolution is affected,
- reaching kLimitReached,
- and reaching unrestricted.
- That "disabled" does not adapt.
- When adaptation is not possible, including...
- kInsufficientInput
- kAwaitingPreviousAdaptation
- kIsBitrateConstrained
- PeekNextRestrictions()
- "balanced" + "screenshare" = "maintain-resolution"
- Change degradation preference to/from "balanced" clears restrictions.
- That using invalidated adaptations triggers DCHECKs.
Bug: webrtc:11393
Change-Id: I28e2cf227bc1fd8871ee0d18d9570d4063449160
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/170625
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30816}
4c07605f8d