Rename Maybe to Optional

webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h

Index: webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h
diff --git a/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h b/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h
index 565c1f349f6697f7569f51198d8f72005e552788..b20d9389b77c8cac8d7b5de5e7361c562d077c05 100644
--- a/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h
+++ b/webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h
@@ -134,7 +134,7 @@ class NonlinearBeamformer
 
   const std::vector<Point> array_geometry_;
   // The normal direction of the array if it has one and it is in the xy-plane.
-  const rtc::Maybe<Point> array_normal_;
+  const rtc::Optional<Point> array_normal_;
 
   // Minimum spacing between microphone pairs.
   const float min_mic_spacing_;