Standardize usage of virtual/override/final in components/

components/visitedlink/test/visitedlink_perftest.cc

Index: components/visitedlink/test/visitedlink_perftest.cc
diff --git a/components/visitedlink/test/visitedlink_perftest.cc b/components/visitedlink/test/visitedlink_perftest.cc
index d4dd5837565a0ad43cc6128426dcade047852485..f3d3dca70d72471a102e5ebb85add513fdbca710 100644
--- a/components/visitedlink/test/visitedlink_perftest.cc
+++ b/components/visitedlink/test/visitedlink_perftest.cc
@@ -39,9 +39,9 @@ GURL TestURL(const char* prefix, int i) {
 class DummyVisitedLinkEventListener : public VisitedLinkMaster::Listener {
  public:
   DummyVisitedLinkEventListener() {}
-  virtual void NewTable(base::SharedMemory* table) override {}
-  virtual void Add(VisitedLinkCommon::Fingerprint) override {}
-  virtual void Reset() override {}
+  void NewTable(base::SharedMemory* table) override {}
+  void Add(VisitedLinkCommon::Fingerprint) override {}
+  void Reset() override {}
 };