Enable -Winconsistent-missing-override flag.

webrtc/base/rtccertificategenerator_unittest.cc

Index: webrtc/base/rtccertificategenerator_unittest.cc
diff --git a/webrtc/base/rtccertificategenerator_unittest.cc b/webrtc/base/rtccertificategenerator_unittest.cc
index 750839cdfdadfe6a7b14510894fced7d717edf30..a6e88a1a866233ec0f53035ea0e63512f7d0427d 100644
--- a/webrtc/base/rtccertificategenerator_unittest.cc
+++ b/webrtc/base/rtccertificategenerator_unittest.cc
@@ -36,13 +36,13 @@ class RTCCertificateGeneratorFixture : public RTCCertificateGeneratorCallback {
   RTCCertificateGenerator* generator() const { return generator_.get(); }
   RTCCertificate* certificate() const { return certificate_.get(); }
 
-  void OnSuccess(const scoped_refptr<RTCCertificate>& certificate) {
+  void OnSuccess(const scoped_refptr<RTCCertificate>& certificate) override {
     RTC_CHECK(signaling_thread_->IsCurrent());
     RTC_CHECK(certificate);
     certificate_ = certificate;
     generate_async_completed_ = true;
   }
-  void OnFailure() {
+  void OnFailure() override {
     RTC_CHECK(signaling_thread_->IsCurrent());
     certificate_ = nullptr;
     generate_async_completed_ = true;