Revert of Remove ignored return code from modules.

webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc

Index: webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc
diff --git a/webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc b/webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc
index 51f93f96ce88a1ceeded24bb3b743d00c80c3cfc..ee17ad78db8b6b5c4e8665cf467b255554e5983c 100644
--- a/webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc
+++ b/webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.cc
@@ -71,9 +71,9 @@
   return time_until_next;
 }
 
-void RemoteEstimatorProxy::Process() {
+int32_t RemoteEstimatorProxy::Process() {
   if (TimeUntilNextProcess() > 0)
-    return;
+    return 0;
   last_process_time_ms_ = clock_->TimeInMilliseconds();
 
   bool more_to_build = true;
@@ -86,6 +86,8 @@
       more_to_build = false;
     }
   }
+
+  return 0;
 }
 
 void RemoteEstimatorProxy::OnPacketArrival(uint16_t sequence_number,