Update from chromium https://crrev.com/301725/

net/quic/test_tools/crypto_test_utils_nss.cc

Index: net/quic/test_tools/crypto_test_utils_nss.cc
diff --git a/net/quic/test_tools/crypto_test_utils_nss.cc b/net/quic/test_tools/crypto_test_utils_nss.cc
index 96fdd313cef0e3a15c0379cfd573b11532576410..f42775003faef05be62576f497c09a54cd04870d 100644
--- a/net/quic/test_tools/crypto_test_utils_nss.cc
+++ b/net/quic/test_tools/crypto_test_utils_nss.cc
@@ -20,13 +20,11 @@ namespace test {
 
 class TestChannelIDSource : public ChannelIDSource {
  public:
-  virtual ~TestChannelIDSource() {
-    STLDeleteValues(&hostname_to_key_);
-  }
+  ~TestChannelIDSource() override { STLDeleteValues(&hostname_to_key_); }
 
   // ChannelIDSource implementation.
 
-  virtual QuicAsyncStatus GetChannelIDKey(
+  QuicAsyncStatus GetChannelIDKey(
       const string& hostname,
       scoped_ptr<ChannelIDKey>* channel_id_key,
       ChannelIDSourceCallback* /*callback*/) override {