Fix flaky test introduced by r16478 and r16492

webrtc/video/end_to_end_tests.cc

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #include <algorithm>
@@ skipping 1075 matching lines @@
           // details.
           observation_complete_.Set();
         }
         return DROP_PACKET;
       }
 
       return SEND_PACKET;
     }
 
     void OnFrame(const VideoFrame& frame) override {
-      rtc::CritScope lock(&crit_);
-      if (frame.timestamp() == retransmitted_timestamp_)
-        observation_complete_.Set();
-      rendered_timestamps_.push_back(frame.timestamp());
+      {
+        rtc::CritScope lock(&crit_);
+        if (frame.timestamp() == retransmitted_timestamp_)
+          observation_complete_.Set();
+        rendered_timestamps_.push_back(frame.timestamp());
+      }
       orig_renderer_->OnFrame(frame);
     }
 
     void ModifyVideoConfigs(
         VideoSendStream::Config* send_config,
         std::vector<VideoReceiveStream::Config>* receive_configs,
         VideoEncoderConfig* encoder_config) override {
       send_config->rtp.nack.rtp_history_ms = kNackRtpHistoryMs;
 
       // Insert ourselves into the rendering pipeline.
       RTC_DCHECK(!orig_renderer_);
       orig_renderer_ = (*receive_configs)[0].renderer;
       RTC_DCHECK(orig_renderer_);
+      (*receive_configs)[0].disable_prerenderer_smoothing = true;
       (*receive_configs)[0].renderer = this;
 
       (*receive_configs)[0].rtp.nack.rtp_history_ms = kNackRtpHistoryMs;
 
       if (payload_type_ == kRedPayloadType) {
         send_config->rtp.ulpfec.ulpfec_payload_type = kUlpfecPayloadType;
         send_config->rtp.ulpfec.red_payload_type = kRedPayloadType;
         if (retransmission_ssrc_ == kSendRtxSsrcs[0])
           send_config->rtp.ulpfec.red_rtx_payload_type = kRtxRedPayloadType;
         (*receive_configs)[0].rtp.ulpfec.ulpfec_payload_type =
@@ skipping 3063 matching lines @@
     std::unique_ptr<VideoEncoder> encoder_;
     std::unique_ptr<VideoDecoder> decoder_;
     rtc::CriticalSection crit_;
     int recorded_frames_ GUARDED_BY(crit_);
   } test(this);
 
   RunBaseTest(&test);
 }
 
 }  // namespace webrtc