Add a placeholder stat for logging the estimated residual echo likelihood.

webrtc/api/statscollector_unittest.cc

Index: webrtc/api/statscollector_unittest.cc
diff --git a/webrtc/api/statscollector_unittest.cc b/webrtc/api/statscollector_unittest.cc
index 8d5978f66f842dd7a4636dc465c0816a949936c4..866e76fdaafa7957dd7b00be044f18b97da32edb 100644
--- a/webrtc/api/statscollector_unittest.cc
+++ b/webrtc/api/statscollector_unittest.cc
@@ -402,8 +402,13 @@ void VerifyVoiceSenderInfoReport(const StatsReport* report,
       &value_in_report));
   EXPECT_EQ(rtc::ToString<int>(sinfo.echo_return_loss_enhancement),
             value_in_report);
-  EXPECT_TRUE(GetValue(
-      report, StatsReport::kStatsValueNameAudioInputLevel, &value_in_report));
+  EXPECT_TRUE(GetValue(report,
+                       StatsReport::kStatsValueNameResidualEchoLikelihood,
+                       &value_in_report));
+  EXPECT_EQ(rtc::ToString<float>(sinfo.residual_echo_likelihood),
+            value_in_report);
+  EXPECT_TRUE(GetValue(report, StatsReport::kStatsValueNameAudioInputLevel,
+                       &value_in_report));
   EXPECT_EQ(rtc::ToString<int>(sinfo.audio_level), value_in_report);
   EXPECT_TRUE(GetValue(
       report, StatsReport::kStatsValueNameTypingNoiseState, &value_in_report));