Add AudioStreamRegistry. Move stream counting logic

content/browser/renderer_host/media/audio_stream_registry_impl_unittest.cc

+// 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 "content/browser/renderer_host/media/audio_stream_registry_impl.h"
+
+#include "base/run_loop.h"
+#include "base/test/histogram_tester.h"
+#include "content/public/test/mock_render_process_host.h"
+#include "content/public/test/test_browser_context.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using testing::StrictMock;
+using testing::ElementsAre;
+using testing::Mock;
+
+namespace content {
+
+namespace {
+
+const int kRenderProcessId = 0;
+
+class MockRenderProcessHostHandler {
+ public:
+  MOCK_METHOD0(AudioStateChanged, void());
+};
+}  // namespace
+
+class AudioStreamRegistryImplTest : public testing::Test {
+ public:
+  AudioStreamRegistryImplTest() = default;
+  ~AudioStreamRegistryImplTest() override = default;
+
+ private:
+  TestBrowserThreadBundle thread_bundle_;
+};
+
+TEST_F(AudioStreamRegistryImplTest, RegisterUnregister) {
+  base::HistogramTester hist;
+  {
+    AudioStreamRegistryImpl registry(kRenderProcessId);
+
+    EXPECT_FALSE(registry.HasActiveAudio());
+    registry.RegisterStream();
+    EXPECT_FALSE(registry.HasActiveAudio());
+    registry.DeregisterStream();
+    EXPECT_FALSE(registry.HasActiveAudio());
+  }
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreams"),
+              ElementsAre(base::Bucket(1, 1)));
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreamsTotal"),
+              ElementsAre(base::Bucket(1, 1)));
+}
+
+TEST_F(AudioStreamRegistryImplTest, RegisterPlayUnregister) {
+  base::HistogramTester hist;
+  {
+    AudioStreamRegistryImpl registry(kRenderProcessId);
+
+    registry.RegisterStream();
+    registry.StreamStateChanged(true);
+    EXPECT_TRUE(registry.HasActiveAudio());
+    registry.StreamStateChanged(false);
+    EXPECT_FALSE(registry.HasActiveAudio());
+    registry.DeregisterStream();
+    EXPECT_FALSE(registry.HasActiveAudio());
+  }
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreams"),
+              ElementsAre(base::Bucket(1, 1)));
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreamsTotal"),
+              ElementsAre(base::Bucket(1, 1)));
+}
+
+TEST_F(AudioStreamRegistryImplTest, MultipleRegistriesSerial) {
+  base::HistogramTester hist;
+  {
+    AudioStreamRegistryImpl registry(kRenderProcessId);
+    AudioStreamRegistryImpl registry2(kRenderProcessId);
+
+    registry.RegisterStream();
+    registry.DeregisterStream();
+    registry2.RegisterStream();
+    registry2.RegisterStream();
+    registry2.DeregisterStream();
+    registry2.DeregisterStream();
+  }
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreams"),
+              ElementsAre(base::Bucket(1, 1), base::Bucket(2, 1)));
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreamsTotal"),
+              ElementsAre(base::Bucket(0, 1), base::Bucket(2, 1)));
+}
+
+TEST_F(AudioStreamRegistryImplTest, MultipleRegistriesConcurrent) {
+  base::HistogramTester hist;
+  {
+    AudioStreamRegistryImpl registry(kRenderProcessId);
+    AudioStreamRegistryImpl registry2(kRenderProcessId);
+
+    registry.RegisterStream();
+    registry2.RegisterStream();
+    registry2.RegisterStream();
+    registry.DeregisterStream();
+    registry2.DeregisterStream();
+    registry2.DeregisterStream();
+  }
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreams"),
+              ElementsAre(base::Bucket(1, 1), base::Bucket(2, 1)));
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreamsTotal"),
+              ElementsAre(base::Bucket(0, 1), base::Bucket(3, 1)));
+}
+
+TEST_F(AudioStreamRegistryImplTest, StateChangeNotifiesRenderProcessHost) {
+  base::HistogramTester hist;
+  {
+    TestBrowserContext context;
+    MockRenderProcessHost rph(&context);
+    StrictMock<MockRenderProcessHostHandler> mock;
+    rph.SetAudioStateChangedCallback(
+        base::Bind(&MockRenderProcessHostHandler::AudioStateChanged,
+                   base::Unretained(&mock)));
+    AudioStreamRegistryImpl registry(rph.GetID());
+
+    registry.RegisterStream();
+    base::RunLoop().RunUntilIdle();
+
+    EXPECT_CALL(mock, AudioStateChanged());
+    registry.StreamStateChanged(true);
+    base::RunLoop().RunUntilIdle();
+    EXPECT_TRUE(Mock::VerifyAndClearExpectations(&mock));
+    EXPECT_CALL(mock, AudioStateChanged());
+    registry.StreamStateChanged(false);
+    base::RunLoop().RunUntilIdle();
+    EXPECT_TRUE(Mock::VerifyAndClearExpectations(&mock));
+    registry.DeregisterStream();
+  }
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreams"),
+              ElementsAre(base::Bucket(1, 1)));
+  EXPECT_THAT(hist.GetAllSamples("Media.AudioRendererIpcStreamsTotal"),
+              ElementsAre(base::Bucket(1, 1)));
+}
+
+}  // namespace content