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

Source/core/page/PageLifecycleNotifier.h

Index: Source/core/page/PageLifecycleNotifier.h
diff --git a/Source/core/platform/PurgeableBuffer.h b/Source/core/page/PageLifecycleNotifier.h
similarity index 52%
copy from Source/core/platform/PurgeableBuffer.h
copy to Source/core/page/PageLifecycleNotifier.h
index 3ad0992e229b2623f6abee13794187735b90425e..8ad03ee6bc9b8d62755d591eaf76426c9d749099 100644
--- a/Source/core/platform/PurgeableBuffer.h
+++ b/Source/core/page/PageLifecycleNotifier.h
@@ -1,5 +1,5 @@
+
 /*
- * Copyright (C) 2008, 2010 Apple Inc. All Rights Reserved.
  * Copyright (C) 2013 Google Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -21,51 +21,49 @@
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef PurgeableBuffer_h
-#define PurgeableBuffer_h
+#ifndef PageLifecycleNotifier_h
+#define PageLifecycleNotifier_h
 
-#include "wtf/OwnPtr.h"
+#include "core/dom/SimpleLifecycleNotifier.h"
+#include "core/page/PageLifecycleObserver.h"
 #include "wtf/PassOwnPtr.h"
-
-namespace WebKit {
-class WebDiscardableMemory;
-}
+#include "wtf/TemporaryChange.h"
 
 namespace WebCore {
 
-class PurgeableBuffer {
-    WTF_MAKE_NONCOPYABLE(PurgeableBuffer);
-public:
-    static PassOwnPtr<PurgeableBuffer> create(const char* data, size_t);
-    ~PurgeableBuffer();
+class Page;
 
-    // Call lock and check the return value before accessing the data.
-    const char* data() const;
-    size_t size() const { return m_size; }
+class PageLifecycleNotifier : public SimpleLifecycleNotifier {
+public:
+    static PassOwnPtr<PageLifecycleNotifier> create(SimpleLifecycleContext*);
 
-    bool isPurgeable() const { return m_state != Locked; }
-    bool wasPurged() const;
+    void notifyPageVisibilityChanged();
 
-    bool lock();
-    void unlock();
+    virtual void addObserver(SimpleLifecycleObserver*, SimpleLifecycleObserver::Type) OVERRIDE;
+    virtual void removeObserver(SimpleLifecycleObserver*, SimpleLifecycleObserver::Type) OVERRIDE;
 
 private:
-    enum State {
-        Locked,
-        Unlocked,
-        Purged
-    };
+    explicit PageLifecycleNotifier(SimpleLifecycleContext*);
 
-    PurgeableBuffer(PassOwnPtr<WebKit::WebDiscardableMemory>, const char* data, size_t);
-
-    OwnPtr<WebKit::WebDiscardableMemory> m_memory;
-    size_t m_size;
-    State m_state;
+    typedef HashSet<PageLifecycleObserver*> PageObserverSet;
+    PageObserverSet m_pageObservers;
 };
 
+inline PassOwnPtr<PageLifecycleNotifier> PageLifecycleNotifier::create(SimpleLifecycleContext* context)
+{
+    return adoptPtr(new PageLifecycleNotifier(context));
+}
+
+inline void PageLifecycleNotifier::notifyPageVisibilityChanged()
+{
+    TemporaryChange<IterationType> scope(this->m_iterating, IteratingOverPageObservers);
+    for (PageObserverSet::iterator it = m_pageObservers.begin(); it != m_pageObservers.end(); ++it)
+        (*it)->pageVisibilityChanged();
 }
 
-#endif
+} // namespace WebCore
+
+#endif // PageLifecycleNotifier_h