RTCStatsCollector: Utilize network thread to minimize thread hops.

webrtc/api/test/mock_webrtcsession.h

Index: webrtc/api/test/mock_webrtcsession.h
diff --git a/webrtc/api/test/mock_webrtcsession.h b/webrtc/api/test/mock_webrtcsession.h
index 108bdcaac09e78feb3ad588123f1750d846036e5..b1e41f6a09892a83338ae04abeda4c0cf52b75bc 100644
--- a/webrtc/api/test/mock_webrtcsession.h
+++ b/webrtc/api/test/mock_webrtcsession.h
@@ -43,9 +43,14 @@ class MockWebRtcSession : public webrtc::WebRtcSession {
   MOCK_METHOD2(GetLocalTrackIdBySsrc, bool(uint32_t, std::string*));
   MOCK_METHOD2(GetRemoteTrackIdBySsrc, bool(uint32_t, std::string*));
   MOCK_METHOD1(GetTransportStats, bool(SessionStats*));
+  MOCK_METHOD1(GetSessionStats_n,
+               std::unique_ptr<SessionStats>(const ChannelNamePairs&));
   MOCK_METHOD2(GetLocalCertificate,
                bool(const std::string& transport_name,
                     rtc::scoped_refptr<rtc::RTCCertificate>* certificate));
+  MOCK_METHOD2(GetLocalCertificate_n,
+               bool(const std::string& transport_name,
+                    rtc::scoped_refptr<rtc::RTCCertificate>* certificate));
 
   // Workaround for gmock's inability to cope with move-only return values.
   std::unique_ptr<rtc::SSLCertificate> GetRemoteSSLCertificate(
@@ -55,6 +60,13 @@ class MockWebRtcSession : public webrtc::WebRtcSession {
   }
   MOCK_METHOD1(GetRemoteSSLCertificate_ReturnsRawPointer,
                rtc::SSLCertificate*(const std::string& transport_name));
+  std::unique_ptr<rtc::SSLCertificate> GetRemoteSSLCertificate_n(
+      const std::string& transport_name) /* override */ {
+    return std::unique_ptr<rtc::SSLCertificate>(
+        GetRemoteSSLCertificate_n_ReturnsRawPointer(transport_name));
+  }
+  MOCK_METHOD1(GetRemoteSSLCertificate_n_ReturnsRawPointer,
+               rtc::SSLCertificate*(const std::string& transport_name));
 };
 
 }  // namespace webrtc