Standardize usage of virtual/override/final in net/

net/dns/dns_test_util.h

Index: net/dns/dns_test_util.h
diff --git a/net/dns/dns_test_util.h b/net/dns/dns_test_util.h
index 5b363c7aa0658bc8d9aab261c6bcd51f26de9173..e168afc4f024bd99ae0c45b27296cc7d8567a35c 100644
--- a/net/dns/dns_test_util.h
+++ b/net/dns/dns_test_util.h
@@ -208,13 +208,13 @@ typedef std::vector<MockDnsClientRule> MockDnsClientRuleList;
 class MockDnsClient : public DnsClient {
  public:
   MockDnsClient(const DnsConfig& config, const MockDnsClientRuleList& rules);
-  virtual ~MockDnsClient();
+  ~MockDnsClient() override;
 
   // DnsClient interface:
-  virtual void SetConfig(const DnsConfig& config) override;
-  virtual const DnsConfig* GetConfig() const override;
-  virtual DnsTransactionFactory* GetTransactionFactory() override;
-  virtual AddressSorter* GetAddressSorter() override;
+  void SetConfig(const DnsConfig& config) override;
+  const DnsConfig* GetConfig() const override;
+  DnsTransactionFactory* GetTransactionFactory() override;
+  AddressSorter* GetAddressSorter() override;
 
   // Completes all DnsTransactions that were delayed by a rule.
   void CompleteDelayedTransactions();