Reland of Deflake ChangingNetworkRoute test.

NOTRY=true
BUG=webrtc:6551

Review-Url: https://codereview.webrtc.org/2451553004
Cr-Commit-Position: refs/heads/master@{#14766}

webrtc/video/video_send_stream_tests.cc

diff --git a/webrtc/video/video_send_stream_tests.cc b/webrtc/video/video_send_stream_tests.cc
index d138893..cc73fa8 100644
--- a/webrtc/video/video_send_stream_tests.cc
+++ b/webrtc/video/video_send_stream_tests.cc
@@ -1274,7 +1274,7 @@
       // that we correctly ignore any packet loss reported prior to that id.
       ++new_route.local_network_id;
       call_->OnNetworkRouteChanged("transport", new_route);
-      EXPECT_EQ(kStartBitrateBps, call_->GetStats().send_bandwidth_bps);
+      EXPECT_GE(call_->GetStats().send_bandwidth_bps, kStartBitrateBps);
     }
 
    private: