Add media constraint-key constants for generating offers and answers

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h

Index: webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h
diff --git a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h
index d57231542d9d07372978f316eff43738c184137a..26a116888a48e1bb0487eb7e85fe4a4b53dda8d7 100644
--- a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h
+++ b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMediaConstraints.h
@@ -14,6 +14,7 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+/** Constraint keys for media sources. */
 RTC_EXTERN NSString * const kRTCMediaConstraintsMinAspectRatio;
 RTC_EXTERN NSString * const kRTCMediaConstraintsMaxAspectRatio;
 RTC_EXTERN NSString * const kRTCMediaConstraintsMaxWidth;
@@ -28,6 +29,13 @@ RTC_EXTERN NSString * const kRTCMediaConstraintsLevelControl;
  */
 RTC_EXTERN NSString * const kRTCMediaConstraintsAudioNetworkAdaptorConfig;
 
+/** Constraint keys for generating offers and answers. */
+RTC_EXTERN NSString * const kRTCMediaConstraintsIceRestart;
+RTC_EXTERN NSString * const kRTCMediaConstraintsOfferToReceiveAudio;
+RTC_EXTERN NSString * const kRTCMediaConstraintsOfferToReceiveVideo;
+RTC_EXTERN NSString * const kRTCMediaConstraintsVoiceActivityDetection;
+
+/** Constraint values for Boolean parameters. */
 RTC_EXTERN NSString * const kRTCMediaConstraintsValueTrue;
 RTC_EXTERN NSString * const kRTCMediaConstraintsValueFalse;