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

Source/web/WebKit.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 53 matching lines @@
 #include "wtf/text/AtomicString.h"
 #include "wtf/text/TextEncoding.h"
 #include <v8.h>
 
 namespace blink {
 
 namespace {
 
 class EndOfTaskRunner : public WebThread::TaskObserver {
 public:
-    virtual void willProcessTask() override
+    void willProcessTask() override
     {
         AnimationClock::notifyTaskStart();
     }
-    virtual void didProcessTask() override
+    void didProcessTask() override
     {
         Microtask::performCheckpoint(mainThreadIsolate());
         V8GCController::reportDOMMemoryUsageToV8(mainThreadIsolate());
         V8Initializer::reportRejectedPromisesOnMainThread();
     }
 };
 
 class MainThreadTaskRunner: public WebThread::Task {
     WTF_MAKE_NONCOPYABLE(MainThreadTaskRunner);
 public:
@@ skipping 205 matching lines @@
     ASSERT(!reloadPages);
     Page::refreshPlugins();
 }
 
 void decommitFreeableMemory()
 {
     WTF::Partitions::decommitFreeableMemory();
 }
 
 } // namespace blink