Minor ObjC header updates.

webrtc/api/objc/RTCDataChannel.h

Index: webrtc/api/objc/RTCDataChannel.h
diff --git a/webrtc/api/objc/RTCDataChannel.h b/webrtc/api/objc/RTCDataChannel.h
index 43f576770236fa5059f9778cd0b7d20c3c390830..59ab2b8b26fddf9706e85d46dfddf5ab4b8daa3b 100644
--- a/webrtc/api/objc/RTCDataChannel.h
+++ b/webrtc/api/objc/RTCDataChannel.h
@@ -8,6 +8,7 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#import <AvailabilityMacros.h>
 #import <Foundation/Foundation.h>
 
 NS_ASSUME_NONNULL_BEGIN
@@ -32,7 +33,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 
 @class RTCDataChannel;
-
 @protocol RTCDataChannelDelegate <NSObject>
 
 /** The data channel state changed. */
@@ -43,7 +43,6 @@ NS_ASSUME_NONNULL_BEGIN
     didReceiveMessageWithBuffer:(RTCDataBuffer *)buffer;
 
 @optional
-
 /** The data channel's |bufferedAmount| changed. */
 - (void)dataChannel:(RTCDataChannel *)dataChannel
     didChangeBufferedAmount:(uint64_t)amount;
@@ -53,12 +52,13 @@ NS_ASSUME_NONNULL_BEGIN
 
 /** Represents the state of the data channel. */
 typedef NS_ENUM(NSInteger, RTCDataChannelState) {
-    RTCDataChannelStateConnecting,
-    RTCDataChannelStateOpen,
-    RTCDataChannelStateClosing,
-    RTCDataChannelStateClosed,
+  RTCDataChannelStateConnecting,
+  RTCDataChannelStateOpen,
+  RTCDataChannelStateClosing,
+  RTCDataChannelStateClosed,
 };
 
+
 @interface RTCDataChannel : NSObject
 
 /**
@@ -67,9 +67,16 @@ typedef NS_ENUM(NSInteger, RTCDataChannelState) {
  */
 @property(nonatomic, readonly) NSString *label;
 
+/** Whether the data channel can send messages in unreliable mode. */
+@property(nonatomic, readonly) BOOL isReliable DEPRECATED_ATTRIBUTE;
+
 /** Returns whether this data channel is ordered or not. */
 @property(nonatomic, readonly) BOOL isOrdered;
 
+/** Deprecated. Use maxPacketLifeTime. */
+@property(nonatomic, readonly) NSUInteger maxRetransmitTime
+    DEPRECATED_ATTRIBUTE;
+
 /**
  * The length of the time window (in milliseconds) during which transmissions
  * and retransmissions may occur in unreliable mode.
@@ -92,6 +99,9 @@ typedef NS_ENUM(NSInteger, RTCDataChannelState) {
  */
 @property(nonatomic, readonly) BOOL isNegotiated;
 
+/** Deprecated. Use channelId. */
+@property(nonatomic, readonly) NSInteger streamId DEPRECATED_ATTRIBUTE;
+
 /** The identifier for this data channel. */
 @property(nonatomic, readonly) int channelId;