Extract simpler classes for observing context lifecycle and observe Page lifecycle inNavigatorVibra…

Source/core/dom/ContextLifecycleObserver.h

Index: Source/core/dom/ContextLifecycleObserver.h
diff --git a/Source/core/dom/ContextLifecycleObserver.h b/Source/core/dom/ContextLifecycleObserver.h
index 574455e861a357cf4f33514367aaf69b3657d5a9..9a258e6f44698bdbc2387af77af1dfebb1a10851 100644
--- a/Source/core/dom/ContextLifecycleObserver.h
+++ b/Source/core/dom/ContextLifecycleObserver.h
@@ -27,26 +27,22 @@
 #ifndef ContextLifecycleObserver_h
 #define ContextLifecycleObserver_h
 
+#include "core/dom/SimpleLifecycleObserver.h"
+
 namespace WebCore {
 
 class ScriptExecutionContext;
 
-class ContextLifecycleObserver {
+class ContextLifecycleObserver : public SimpleLifecycleObserver {
 public:
-    enum Type {
-        ActiveDOMObjectType,
-        DocumentLifecycleObserverType,
-        GenericType
-    };
-
     explicit ContextLifecycleObserver(ScriptExecutionContext*, Type = GenericType);
-    virtual void contextDestroyed();
+
+    virtual void contextDestroyed() OVERRIDE;
 
     ScriptExecutionContext* scriptExecutionContext() const { return m_scriptExecutionContext; }
 
 protected:
     virtual ~ContextLifecycleObserver();
-    void observeContext(ScriptExecutionContext*, Type);
 
     ScriptExecutionContext* m_scriptExecutionContext;
 };