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

webrtc/media/engine/webrtcvoiceengine_unittest.cc

Index: webrtc/media/engine/webrtcvoiceengine_unittest.cc
diff --git a/webrtc/media/engine/webrtcvoiceengine_unittest.cc b/webrtc/media/engine/webrtcvoiceengine_unittest.cc
index 80c3fda2716cacac7f197c957214b8755a538895..f3831f849bbeb6cc3d732f241371a29f186aaaf3 100644
--- a/webrtc/media/engine/webrtcvoiceengine_unittest.cc
+++ b/webrtc/media/engine/webrtcvoiceengine_unittest.cc
@@ -397,6 +397,7 @@ class WebRtcVoiceEngineTestFake : public testing::Test {
     stats.echo_delay_std_ms = 567;
     stats.echo_return_loss = 890;
     stats.echo_return_loss_enhancement = 1234;
+    stats.residual_echo_likelihood = 0.432f;
     stats.typing_noise_detected = true;
     return stats;
   }
@@ -424,6 +425,7 @@ class WebRtcVoiceEngineTestFake : public testing::Test {
     EXPECT_EQ(info.echo_return_loss, stats.echo_return_loss);
     EXPECT_EQ(info.echo_return_loss_enhancement,
               stats.echo_return_loss_enhancement);
+    EXPECT_EQ(info.residual_echo_likelihood, stats.residual_echo_likelihood);
     EXPECT_EQ(info.typing_noise_detected,
               stats.typing_noise_detected && is_sending);
   }