Standardize usage of virtual/override/final specifiers.

content/browser/media/webrtc_identity_store_unittest.cc

Index: content/browser/media/webrtc_identity_store_unittest.cc
diff --git a/content/browser/media/webrtc_identity_store_unittest.cc b/content/browser/media/webrtc_identity_store_unittest.cc
index 9b8c0a19c3b3eb55c2db7375d9b7dcda97fedf58..9078f1a19ac3d4a408ae97681e8fd39e5254b487 100644
--- a/content/browser/media/webrtc_identity_store_unittest.cc
+++ b/content/browser/media/webrtc_identity_store_unittest.cc
@@ -49,9 +49,7 @@ class WebRTCIdentityStoreTest : public testing::Test {
     webrtc_identity_store_->SetTaskRunnerForTesting(pool_owner_->pool());
   }
 
-  virtual ~WebRTCIdentityStoreTest() {
-    pool_owner_->pool()->Shutdown();
-  }
+  ~WebRTCIdentityStoreTest() override { pool_owner_->pool()->Shutdown(); }
 
   void SetValidityPeriod(base::TimeDelta validity_period) {
     webrtc_identity_store_->SetValidityPeriodForTesting(validity_period);