Update inspector classes to use OVERRIDE / FINAL when needed

Source/core/inspector/AsyncCallStackTracker.cpp

Index: Source/core/inspector/AsyncCallStackTracker.cpp
diff --git a/Source/core/inspector/AsyncCallStackTracker.cpp b/Source/core/inspector/AsyncCallStackTracker.cpp
index 7c264a3bd220b79d75701aa72c5a88a1f1b8c58c..508d4cd24a9dcda9e89ebc23a380f982b32f4b88 100644
--- a/Source/core/inspector/AsyncCallStackTracker.cpp
+++ b/Source/core/inspector/AsyncCallStackTracker.cpp
@@ -53,7 +53,7 @@ static const char enqueueMutationRecordName[] = "Mutation";
 
 namespace WebCore {
 
-class AsyncCallStackTracker::ExecutionContextData : public ContextLifecycleObserver {
+class AsyncCallStackTracker::ExecutionContextData FINAL : public ContextLifecycleObserver {
     WTF_MAKE_FAST_ALLOCATED;
 public:
     typedef std::pair<RegisteredEventListener, RefPtr<AsyncCallChain> > EventListenerAsyncCallChain;