Add histograms WebRTC.Audio.Agc.ClippingPredictor.Precision and WebRTC.Audio.Agc.ClippingPredictor.Recall. The histograms are defined in https://chromium-review.googlesource.com/c/chromium/src/+/3150271. Bug: webrtc:12774 Change-Id: I1561ec7a61377c262f636d7aa3a5d5fd60a8839d Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/231460 Commit-Queue: Hanna Silen <silen@webrtc.org> Reviewed-by: Alessio Bazzica <alessiob@webrtc.org> Cr-Commit-Position: refs/heads/main@{#35083}