Standardize usage of virtual/override/final in components/

components/policy/core/common/preferences_mock_mac.h

Index: components/policy/core/common/preferences_mock_mac.h
diff --git a/components/policy/core/common/preferences_mock_mac.h b/components/policy/core/common/preferences_mock_mac.h
index 1ae517ed1bf598cd52c39d1b232dbb67c0c597c8..8f3df0c8c7783b16fd541a138e069babc7620713 100644
--- a/components/policy/core/common/preferences_mock_mac.h
+++ b/components/policy/core/common/preferences_mock_mac.h
@@ -13,15 +13,14 @@
 class POLICY_EXPORT MockPreferences : public MacPreferences {
  public:
   MockPreferences();
-  virtual ~MockPreferences();
+  ~MockPreferences() override;
 
-  virtual Boolean AppSynchronize(CFStringRef applicationID) override;
+  Boolean AppSynchronize(CFStringRef applicationID) override;
 
-  virtual CFPropertyListRef CopyAppValue(CFStringRef key,
-                                         CFStringRef applicationID) override;
+  CFPropertyListRef CopyAppValue(CFStringRef key,
+                                 CFStringRef applicationID) override;
 
-  virtual Boolean AppValueIsForced(CFStringRef key,
-                                   CFStringRef applicationID) override;
+  Boolean AppValueIsForced(CFStringRef key, CFStringRef applicationID) override;
 
   // Adds a preference item with the given info to the test set.
   void AddTestItem(CFStringRef key, CFPropertyListRef value, bool is_forced);