Propagate bitrate setting to RTCRtpSender.

webrtc/examples/objc/AppRTCMobile/ARDAppClient.m

Index: webrtc/examples/objc/AppRTCMobile/ARDAppClient.m
diff --git a/webrtc/examples/objc/AppRTCMobile/ARDAppClient.m b/webrtc/examples/objc/AppRTCMobile/ARDAppClient.m
index cfcb3565483c9f9e04a8c1f49232b0aaf74b4fd3..40a2be7cbf8cc3ec5d2c96f10d7693ba2504dcd7 100644
--- a/webrtc/examples/objc/AppRTCMobile/ARDAppClient.m
+++ b/webrtc/examples/objc/AppRTCMobile/ARDAppClient.m
@@ -50,12 +50,14 @@ static NSInteger const kARDAppClientErrorInvalidRoom = -6;
 static NSString * const kARDMediaStreamId = @"ARDAMS";
 static NSString * const kARDAudioTrackId = @"ARDAMSa0";
 static NSString * const kARDVideoTrackId = @"ARDAMSv0";
+static NSString * const kARDVideoTrackKind = @"video";
 
 // TODO(tkchin): Add these as UI options.
 static BOOL const kARDAppClientEnableTracing = NO;
 static BOOL const kARDAppClientEnableRtcEventLog = YES;
 static int64_t const kARDAppClientAecDumpMaxSizeInBytes = 5e6;  // 5 MB.
 static int64_t const kARDAppClientRtcEventLogMaxSizeInBytes = 5e6;  // 5 MB.
+static int const kKbpsMultiplier = 1000;
 
 // We need a proxy to NSTimer because it causes a strong retain cycle. When
 // using the proxy, |invalidate| must be called before it properly deallocs.
@@ -476,6 +478,7 @@ static int64_t const kARDAppClientRtcEventLogMaxSizeInBytes = 5e6;  // 5 MB.
         [[ARDSessionDescriptionMessage alloc]
             initWithDescription:sdpPreferringH264];
     [self sendSignalingMessage:message];
+    [self setMaxBitrateForPeerConnectionVideoSender];
   });
 }
 
@@ -680,21 +683,35 @@ static int64_t const kARDAppClientRtcEventLogMaxSizeInBytes = 5e6;  // 5 MB.
   RTCRtpSender *sender =
       [_peerConnection senderWithKind:kRTCMediaStreamTrackKindVideo
                              streamId:kARDMediaStreamId];
-
-  [self setMaxBitrate:_maxBitrate forVideoSender:sender];
-
   RTCVideoTrack *track = [self createLocalVideoTrack];
   if (track) {
     sender.track = track;
     [_delegate appClient:self didReceiveLocalVideoTrack:track];
   }
+
   return sender;
 }
 
+- (void)setMaxBitrateForPeerConnectionVideoSender {
+  for (RTCRtpSender *sender in _peerConnection.senders) {
+    if (sender.track != nil) {
+      if ([sender.track.kind isEqualToString:kARDVideoTrackKind]) {
+        [self setMaxBitrate:_maxBitrate forVideoSender:sender];
+      }
+    }
+  }
+}
+
 - (void)setMaxBitrate:(NSNumber *)maxBitrate forVideoSender:(RTCRtpSender *)sender {
-  for (RTCRtpEncodingParameters *encoding in sender.parameters.encodings) {
-    encoding.maxBitrateBps = maxBitrate;
+  if (maxBitrate.intValue <= 0) {
+    return;
+  }
+
+  RTCRtpParameters *parametersToModify = sender.parameters;
+  for (RTCRtpEncodingParameters *encoding in parametersToModify.encodings) {
+    encoding.maxBitrateBps = @(maxBitrate.intValue * kKbpsMultiplier);
   }
+  [sender setParameters:parametersToModify];
 }
 
 - (RTCRtpSender *)createAudioSender {