Unify AdaptationReason and AdaptReason enums.

Moves the unified AdaptationReason to the api/ folder.

Bug: webrtc:11392
Change-Id: I28782e82ef6cc3ca3b061f65b0bbdc3766df1f9c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/172583
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31084}
diff --git a/video/adaptation/quality_scaler_resource.h b/video/adaptation/quality_scaler_resource.h
index 7708710..77bb606 100644
--- a/video/adaptation/quality_scaler_resource.h
+++ b/video/adaptation/quality_scaler_resource.h
@@ -14,6 +14,7 @@
 #include <memory>
 #include <string>
 
+#include "api/video/video_adaptation_reason.h"
 #include "api/video_codecs/video_encoder.h"
 #include "call/adaptation/resource.h"
 #include "modules/video_coding/utility/quality_scaler.h"
@@ -46,8 +47,8 @@
   // AdaptationObserverInterface implementation.
   // TODO(https://crbug.com/webrtc/11222, 11172): This resource also needs to
   // signal when its stable to support multi-stream aware modules.
-  void AdaptUp(AdaptReason reason) override;
-  bool AdaptDown(AdaptReason reason) override;
+  void AdaptUp(VideoAdaptationReason reason) override;
+  bool AdaptDown(VideoAdaptationReason reason) override;
 
   std::string name() const override { return "QualityScalerResource"; }