First version of PerformanceObserver

Source/core/timing/PerformanceObserver.h

+/*
+ * Copyright (C) 2015 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:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR 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.
+ */
+
+#ifndef PerformanceObserver_h
+#define PerformanceObserver_h
+
+#include "bindings/core/v8/ScriptWrappable.h"
+#include "platform/heap/Handle.h"
+#include "wtf/HashSet.h"
+#include "wtf/PassOwnPtr.h"
+#include "wtf/PassRefPtr.h"
+#include "wtf/RefCounted.h"
+#include "wtf/RefPtr.h"
+#include "wtf/Vector.h"
+
+namespace blink {
+
+class ExceptionState;
+class PerformanceBase;
+class PerformanceObserverCallback;
+class PerformanceObserver;
+class PerformanceObserverInit;
+class PerformanceObserverRegistration;
+class PerformanceEntry;
+
+using PerformanceObserverSet = HeapHashSet<Member<PerformanceObserver>>;
+using PerformanceObserverVector = HeapVector<Member<PerformanceObserver>>;
+using PerformanceEntryVector = HeapVector<Member<PerformanceEntry>>;
+using PerformanceObserverRegistrationSet = HeapHashSet<WeakMember<PerformanceObserverRegistration>>;
+
+class PerformanceObserver final : public GarbageCollectedFinalized<PerformanceObserver>, public ScriptWrappable {
+    DEFINE_WRAPPERTYPEINFO();
+public:
+
+    static PerformanceObserver* create(PerformanceBase*, PerformanceObserverCallback*);
+    static void resumeSuspendedObservers();
+    static void deliverObservations();
+
+    ~PerformanceObserver();
+
+    void observe(const PerformanceObserverInit&, ExceptionState&);
+    void disconnect();
+    void observationStarted(PerformanceObserverRegistration*);
+    void observationEnded(PerformanceObserverRegistration*);
+    void enqueuePerformanceEntry(PerformanceEntry*);
+
+    // Eagerly finalized as destructor accesses heap object members.
+    EAGERLY_FINALIZE();
+    DECLARE_TRACE();
+
+private:
+    struct ObserverLessThan;
+
+    explicit PerformanceObserver(PerformanceBase*, PerformanceObserverCallback*);
+    void deliver();
+    bool shouldBeSuspended() const;
+
+    Member<PerformanceObserverCallback> m_callback;
+    WeakMember<PerformanceBase> m_performance;
+    PerformanceEntryVector m_performanceEntries;
+    PerformanceObserverRegistrationSet m_registrations;
+    unsigned m_priority;
+};
+
+} // namespace blink
+
+#endif // PerformanceObserver_h