Replace FINAL and OVERRIDE with their C++11 counterparts in Source/core/testing

Source/core/testing/NullExecutionContext.cpp

Index: Source/core/testing/NullExecutionContext.cpp
diff --git a/Source/core/testing/NullExecutionContext.cpp b/Source/core/testing/NullExecutionContext.cpp
index 028c049dd1e437348a5d853f4bbb63ae08365607..eed3e17e5c66d4026127de8f8ad4d956bfd5d20b 100644
--- a/Source/core/testing/NullExecutionContext.cpp
+++ b/Source/core/testing/NullExecutionContext.cpp
@@ -13,13 +13,13 @@ namespace blink {
 
 namespace {
 
-class NullEventQueue FINAL : public EventQueue {
+class NullEventQueue final : public EventQueue {
 public:
     NullEventQueue() { }
     virtual ~NullEventQueue() { }
-    virtual bool enqueueEvent(PassRefPtrWillBeRawPtr<Event>) OVERRIDE { return true; }
-    virtual bool cancelEvent(Event*) OVERRIDE { return true; }
-    virtual void close() OVERRIDE { }
+    virtual bool enqueueEvent(PassRefPtrWillBeRawPtr<Event>) override { return true; }
+    virtual bool cancelEvent(Event*) override { return true; }
+    virtual void close() override { }
 };
 
 } // namespace