Simplify lifecycle notifiers and observers.

Source/platform/LifecycleContextTest.cpp

 /*
  * Copyright (C) 2013 Google 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 16 matching lines @@
 #include "config.h"
 
 #include "platform/LifecycleNotifier.h"
 #include "platform/heap/Handle.h"
 #include <gtest/gtest.h>
 
 using namespace blink;
 
 namespace blink {
 
-class DummyContext final : public NoBaseWillBeGarbageCollectedFinalized<DummyContext>, public LifecycleNotifier<DummyContext> {
+class TestingObserver;
+
+class DummyContext final : public NoBaseWillBeGarbageCollectedFinalized<DummyContext>, public LifecycleNotifier<DummyContext, TestingObserver> {
 public:
     DummyContext()
-        : LifecycleNotifier<DummyContext>(this)
+        : LifecycleNotifier<DummyContext, TestingObserver>(this)
     {
     }
 
+    void addObserver(TestingObserver* observer)
+    {
+        LifecycleNotifier<DummyContext, TestingObserver>::addObserver(observer);
+    }
+
+    void removeObserver(TestingObserver* observer)
+    {
+        LifecycleNotifier<DummyContext, TestingObserver>::removeObserver(observer);
+    }
+
     DEFINE_INLINE_TRACE()
     {
-        LifecycleNotifier<DummyContext>::trace(visitor);
+        LifecycleNotifier<DummyContext, TestingObserver>::trace(visitor);
     }
 };
 
-template<> void observeContext(DummyContext* context, LifecycleObserver<DummyContext>* observer)
-{
-    context->addObserver(observer);
-}
-
-template<> void unobserveContext(DummyContext* context, LifecycleObserver<DummyContext>* observer)
-{
-    context->removeObserver(observer);
-}
-
-class TestingObserver final : public GarbageCollectedFinalized<TestingObserver>, public LifecycleObserver<DummyContext> {
+class TestingObserver final : public NoBaseWillBeGarbageCollectedFinalized<TestingObserver>, public LifecycleObserver<DummyContext, TestingObserver, DummyContext> {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(TestingObserver);
 public:
     explicit TestingObserver(DummyContext* context)
-        : LifecycleObserver<DummyContext>(context)
+        : LifecycleObserver<DummyContext, TestingObserver, DummyContext>(context)
         , m_contextDestroyedCalled(false)
-    { }
+    {
+        setContext(context);
+    }
 
     virtual void contextDestroyed() override
     {
-        LifecycleObserver<DummyContext>::contextDestroyed();
+        LifecycleObserver<DummyContext, TestingObserver, DummyContext>::contextDestroyed();
         m_contextDestroyedCalled = true;
     }
 
     DEFINE_INLINE_TRACE()
     {
-        LifecycleObserver<DummyContext>::trace(visitor);
+        LifecycleObserver<DummyContext, TestingObserver, DummyContext>::trace(visitor);
     }
 
     bool m_contextDestroyedCalled;
 
     void unobserve() { setContext(nullptr); }
 };
 
 TEST(LifecycleContextTest, shouldObserveContextDestroyed)
 {
     OwnPtrWillBeRawPtr<DummyContext> context = adoptPtrWillBeNoop(new DummyContext());
-    Persistent<TestingObserver> observer = new TestingObserver(context.get());
+    OwnPtrWillBePersistent<TestingObserver> observer = adoptPtrWillBeNoop(new TestingObserver(context.get()));
 
     EXPECT_EQ(observer->lifecycleContext(), context.get());
     EXPECT_FALSE(observer->m_contextDestroyedCalled);
     context->notifyContextDestroyed();
     context = nullptr;
     Heap::collectAllGarbage();
     EXPECT_EQ(observer->lifecycleContext(), static_cast<DummyContext*>(0));
     EXPECT_TRUE(observer->m_contextDestroyedCalled);
 }
 
 TEST(LifecycleContextTest, shouldNotObserveContextDestroyedIfUnobserve)
 {
     OwnPtrWillBeRawPtr<DummyContext> context = adoptPtrWillBeNoop(new DummyContext());
-    Persistent<TestingObserver> observer = new TestingObserver(context.get());
+    OwnPtrWillBePersistent<TestingObserver> observer = adoptPtrWillBeNoop(new TestingObserver(context.get()));
     observer->unobserve();
     context->notifyContextDestroyed();
     context = nullptr;
     Heap::collectAllGarbage();
     EXPECT_EQ(observer->lifecycleContext(), static_cast<DummyContext*>(0));
     EXPECT_FALSE(observer->m_contextDestroyedCalled);
 }
 
 }