Fix an edge case where early disconnect() can omit delivering of observation. crbug/607324

third_party/WebKit/Source/core/timing/PerformanceBaseTest.cpp

Index: third_party/WebKit/Source/core/timing/PerformanceBaseTest.cpp
diff --git a/third_party/WebKit/Source/core/timing/PerformanceBaseTest.cpp b/third_party/WebKit/Source/core/timing/PerformanceBaseTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..8b7c6f0b13804d40e1b98648d4a6fb13bda15221
--- /dev/null
+++ b/third_party/WebKit/Source/core/timing/PerformanceBaseTest.cpp
@@ -0,0 +1,91 @@
+// Copyright 2016 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 "core/timing/Performance.h"
+
+#include "core/timing/PerformanceBase.h"
+#include "core/timing/PerformanceObserver.h"
+#include "core/timing/PerformanceObserverCallback.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class TestPerformanceBase : public PerformanceBase {
+public:
+    TestPerformanceBase() : PerformanceBase(0) {}
+    ~TestPerformanceBase() {}
+
+    ExecutionContext* getExecutionContext() const override { return nullptr; }
+
+    int numActiveObservers() { return m_activeObservers.size(); }
+
+    int numObservers() { return m_observers.size(); }
+
+    DEFINE_INLINE_TRACE()
+    {
+        PerformanceBase::trace(visitor);
+    }
+};
+
+class MockPerformanceObserverCallback : public PerformanceObserverCallback {
+public:
+    MockPerformanceObserverCallback() {}
+    ~MockPerformanceObserverCallback() {}
+
+    void handleEvent(PerformanceObserverEntryList*, PerformanceObserver*) override {}
+    ExecutionContext* getExecutionContext() const override { return nullptr; }
+
+    DEFINE_INLINE_TRACE()
+    {
+        PerformanceObserverCallback::trace(visitor);
+    }
+};
+
+class PerformanceBaseTest : public ::testing::Test {
+protected:
+    void SetUp() override
+    {
+        m_base = new TestPerformanceBase();
+        m_cb = new MockPerformanceObserverCallback();
+        m_observer = PerformanceObserver::create(m_base, m_cb);
+    }
+
+    Persistent<TestPerformanceBase> m_base;
+    Persistent<PerformanceObserver> m_observer;
+    Persistent<MockPerformanceObserverCallback> m_cb;
+};
+
+TEST_F(PerformanceBaseTest, Register)
+{
+    EXPECT_EQ(0, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+
+    m_base->registerPerformanceObserver(*m_observer.get());
+    EXPECT_EQ(1, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+
+    m_base->unregisterPerformanceObserver(*m_observer.get());
+    EXPECT_EQ(0, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+}
+
+TEST_F(PerformanceBaseTest, Activate)
+{
+    EXPECT_EQ(0, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+
+    m_base->registerPerformanceObserver(*m_observer.get());
+    EXPECT_EQ(1, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+
+    m_base->activateObserver(*m_observer.get());
+    EXPECT_EQ(1, m_base->numObservers());
+    EXPECT_EQ(1, m_base->numActiveObservers());
+
+    m_base->unregisterPerformanceObserver(*m_observer.get());
+    EXPECT_EQ(0, m_base->numObservers());
+    EXPECT_EQ(0, m_base->numActiveObservers());
+}
+
+} // namespace blink