Enable send-side BWE by default.

webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm

Index: webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm
diff --git a/webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm b/webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm
index 38c293f0ecd7a698e9b5be14e38e0c59fb403c50..6e4230de88d9e38dd65f1089aca30c0b78ae0dea 100644
--- a/webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm
+++ b/webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm
@@ -16,15 +16,10 @@
 
 #include "webrtc/system_wrappers/include/field_trial_default.h"
 
-static NSString * const kRTCEnableSendSideBweString =
-    @"WebRTC-SendSideBwe/Enabled/";
 static std::unique_ptr<char[]> gFieldTrialInitString;
 
 void RTCInitFieldTrials(RTCFieldTrialOptions options) {
   NSMutableString *fieldTrialInitString = [NSMutableString string];
-  if (options & RTCFieldTrialOptionsSendSideBwe) {
-    [fieldTrialInitString appendString:kRTCEnableSendSideBweString];
-  }
   size_t len = fieldTrialInitString.length + 1;
   gFieldTrialInitString.reset(new char[len]);
   if (![fieldTrialInitString getCString:gFieldTrialInitString.get()