Fix virtual/override/final usage in the rest of Source/core/.

Source/core/inspector/InspectorHistory.cpp

Index: Source/core/inspector/InspectorHistory.cpp
diff --git a/Source/core/inspector/InspectorHistory.cpp b/Source/core/inspector/InspectorHistory.cpp
index d3ccbceef196bbf39b70819fd85aad442deac4d8..9d5fda7ca94cf10f2540e10631a32f1ad7ff2ca0 100644
--- a/Source/core/inspector/InspectorHistory.cpp
+++ b/Source/core/inspector/InspectorHistory.cpp
@@ -43,13 +43,13 @@ class UndoableStateMark final : public InspectorHistory::Action {
 public:
     UndoableStateMark() : InspectorHistory::Action("[UndoableState]") { }
 
-    virtual bool perform(ExceptionState&) override { return true; }
+    bool perform(ExceptionState&) override { return true; }
 
-    virtual bool undo(ExceptionState&) override { return true; }
+    bool undo(ExceptionState&) override { return true; }
 
-    virtual bool redo(ExceptionState&) override { return true; }
+    bool redo(ExceptionState&) override { return true; }
 
-    virtual bool isUndoableStateMark() override { return true; }
+    bool isUndoableStateMark() override { return true; }
 };
 
 }