Simplify lifecycle notifiers and observers.

Source/core/dom/ContextLifecycleObserver.cpp

 /*
  * Copyright (C) 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 14 matching lines @@
  */
 
 #include "config.h"
 #include "core/dom/ContextLifecycleObserver.h"
 
 #include "core/dom/ContextLifecycleNotifier.h"
 #include "core/dom/ExecutionContext.h"
 
 namespace blink {
 
-template<> void observeContext(ExecutionContext* context, LifecycleObserver<ExecutionContext>* observer)
+ContextLifecycleObserver::ContextLifecycleObserver(ExecutionContext* executionContext, Type type)
+    : LifecycleObserver<ExecutionContext, ContextLifecycleObserver, ContextLifecycleNotifier>(executionContext)
+    , m_observerType(type)
 {
-    context->addObserver(observer);
-}
-
-template<> void unobserveContext(ExecutionContext* context, LifecycleObserver<ExecutionContext>* observer)
-{
-    context->removeObserver(observer);
-}
-
-ContextLifecycleObserver::ContextLifecycleObserver(ExecutionContext* executionContext, Type type)
-    : LifecycleObserver<ExecutionContext>(executionContext, type)
-{
+    setContext(executionContext);
 }
 
 ContextLifecycleObserver::~ContextLifecycleObserver()
 {
 }
 
 } // namespace blink