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

Source/core/dom/custom/CustomElementRegistry.cpp

Index: Source/core/dom/custom/CustomElementRegistry.cpp
diff --git a/Source/core/dom/custom/CustomElementRegistry.cpp b/Source/core/dom/custom/CustomElementRegistry.cpp
index a3b9775947ca47e3be8beaadbe578a655a2edc81..985566f1858836d47b2c966cfd88b3f11e423eed 100644
--- a/Source/core/dom/custom/CustomElementRegistry.cpp
+++ b/Source/core/dom/custom/CustomElementRegistry.cpp
@@ -53,9 +53,9 @@ public:
 private:
 #if ENABLE(OILPAN)
     // In oilpan we don't have the disposed phase for context lifecycle observer.
-    virtual void documentWasDetached() OVERRIDE { m_wentAway = true; }
+    virtual void documentWasDetached() override { m_wentAway = true; }
 #else
-    virtual void documentWasDisposed() OVERRIDE { m_wentAway = true; }
+    virtual void documentWasDisposed() override { m_wentAway = true; }
 #endif
 
     bool m_wentAway;