First version of PerformanceObserver

Source/core/timing/PerformanceObserver.cpp

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "core/timing/PerformanceObserver.h"
+
+#include "bindings/core/v8/ExceptionState.h"
+#include "core/dom/ExceptionCode.h"
+#include "core/inspector/InspectorInstrumentation.h"
+#include "core/timing/PerformanceBase.h"
+#include "core/timing/PerformanceEntry.h"
+#include "core/timing/PerformanceObserverCallback.h"
+#include "core/timing/PerformanceObserverEntryList.h"
+#include "core/timing/PerformanceObserverInit.h"
+#include "platform/Timer.h"
+#include "wtf/MainThread.h"
+#include <algorithm>
+
+namespace blink {
+
+PerformanceObserver* PerformanceObserver::create(PerformanceBase* performance, PerformanceObserverCallback* callback)
+{
+    ASSERT(isMainThread());
+    return new PerformanceObserver(performance, callback);
+}
+
+PerformanceObserver::PerformanceObserver(PerformanceBase* performance, PerformanceObserverCallback* callback)
+    : m_callback(callback)
+    , m_performance(performance)
+    , m_filterOptions(PerformanceEntry::Invalid)
+    , m_isRegistered(false)
+{
+}
+
+PerformanceObserver::~PerformanceObserver()
+{
+    if (!m_performanceEntries.isEmpty())
+        InspectorInstrumentation::didClearAllPerformanceObservations(m_callback->executionContext(), this);
+}
+
+void PerformanceObserver::observe(const PerformanceObserverInit& observerInit, ExceptionState& exceptionState)
+{
+    if (!m_performance) {
+        exceptionState.throwTypeError("Window may be destroyed? Performance target is invalid.");
+        return;
+    }
+
+    PerformanceEntryTypeMask entryTypes = PerformanceEntry::Invalid;
+    if (observerInit.hasEntryTypes() && observerInit.entryTypes().size()) {
+        const Vector<String>& sequence = observerInit.entryTypes();
+        for (unsigned i = 0; i < sequence.size(); ++i)

[esprehn, 2015/08/20 08:33:48]

You can use range loops.

for (const auto& item : items)

[MikeB, 2015/08/25 19:42:42]

Done.

+            entryTypes |= PerformanceEntry::toEntryTypeEnum(sequence[i]);
+    }
+    if (entryTypes == PerformanceEntry::Invalid) {
+        exceptionState.throwTypeError("A Performance Observer MUST have a non-empty entryTypes attribute.");
+        return;
+    }
+    if (m_isRegistered)
+        m_performance->unregisterPerformanceObserver(*this);

[esprehn, 2015/08/20 08:33:48]

Why unregister? I think you just want to only register if you aren't already? I
guess you're trying to update the observation types? You might just add a
function for that explicitly instead.

[MikeB, 2015/08/25 19:42:42]

Done.

+    m_filterOptions = entryTypes;
+    m_performance->registerPerformanceObserver(*this);
+    m_isRegistered = true;
+}
+
+void PerformanceObserver::disconnect()
+{
+    m_performanceEntries.clear();
+    InspectorInstrumentation::didClearAllPerformanceObservations(m_callback->executionContext(), this);
+    if (m_performance)
+        m_performance->unregisterPerformanceObserver(*this);
+    m_isRegistered = false;
+}
+
+void PerformanceObserver::enqueuePerformanceEntry(PerformanceEntry& entry)
+{
+    ASSERT(isMainThread());
+    m_performanceEntries.append(&entry);
+    if (m_performance)
+        m_performance->activateObserver(*this);
+    InspectorInstrumentation::didEnqueuePerformanceObserverEntries(m_callback->executionContext(), this);
+}
+
+bool PerformanceObserver::shouldBeSuspended() const
+{
+    return m_callback->executionContext() && m_callback->executionContext()->activeDOMObjectsAreSuspended();
+}
+
+void PerformanceObserver::deliver()
+{
+    ASSERT(!shouldBeSuspended());
+
+    if (m_performanceEntries.isEmpty())
+        return;
+
+    PerformanceEntryVector performanceEntries;
+    performanceEntries.swap(m_performanceEntries);
+    Member<PerformanceObserverEntryList> entryList(new PerformanceObserverEntryList(performanceEntries));
+
+    InspectorInstrumentation::willDeliverPerformanceObservations(m_callback->executionContext(), this);
+    m_callback->handleEvent(entryList, this);
+    InspectorInstrumentation::didDeliverPerformanceObservations(m_callback->executionContext());
+}
+
+DEFINE_TRACE(PerformanceObserver)
+{
+    visitor->trace(m_callback);
+    visitor->trace(m_performance);
+    visitor->trace(m_performanceEntries);
+}
+
+} // namespace blink