Fix virtual/override/final usage in Source/web/.

Source/web/DatabaseClientImpl.h

Index: Source/web/DatabaseClientImpl.h
diff --git a/Source/web/DatabaseClientImpl.h b/Source/web/DatabaseClientImpl.h
index 6b8b6feffeb7a12e7a34894ae1a7e91046796361..6f51a4d8be7f7cd8799cbda1e212352ac8e818e4 100644
--- a/Source/web/DatabaseClientImpl.h
+++ b/Source/web/DatabaseClientImpl.h
@@ -41,10 +41,10 @@ class DatabaseClientImpl final : public NoBaseWillBeGarbageCollectedFinalized<Da
 public:
     static PassOwnPtrWillBeRawPtr<DatabaseClientImpl> create();
 
-    virtual ~DatabaseClientImpl();
+    ~DatabaseClientImpl() override;
     DECLARE_VIRTUAL_TRACE();
 
-    virtual bool allowDatabase(ExecutionContext*, const String& name, const String& displayName, unsigned long estimatedSize) override;
+    bool allowDatabase(ExecutionContext*, const String& name, const String& displayName, unsigned long estimatedSize) override;
 
 private:
     DatabaseClientImpl();