Add tests for cpu overuse scaling.

Test that adapt down is triggered on overuse for different degradation preference configurations.

Bug: none
Change-Id: I326e979c10d09d17a7c1e6ece9a719f5fd4bff5f
Reviewed-on: https://webrtc-review.googlesource.com/c/97303
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Commit-Queue: Åsa Persson <asapersson@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25611}
diff --git a/video/BUILD.gn b/video/BUILD.gn
index bc8b5a5..824f1c1 100644
--- a/video/BUILD.gn
+++ b/video/BUILD.gn
@@ -411,6 +411,7 @@
     defines = []
     sources = [
       "call_stats_unittest.cc",
+      "cpu_scaling_tests.cc",
       "encoder_rtcp_feedback_unittest.cc",
       "end_to_end_tests/bandwidth_tests.cc",
       "end_to_end_tests/call_operation_tests.cc",