Add mojo interface for audio rendering.

content/browser/renderer_host/media/audio_output_service_context.h

+// Copyright 2017 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.
+
+#ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_OUTPUT_SERVICE_CONTEXT_H_
+#define CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_OUTPUT_SERVICE_CONTEXT_H_
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "content/browser/renderer_host/media/audio_output_authorization_handler.h"
+#include "content/browser/renderer_host/media/audio_output_delegate.h"
+#include "content/common/content_export.h"
+#include "media/mojo/interfaces/audio_output.mojom.h"
+#include "mojo/public/cpp/bindings/interface_request.h"
+
+namespace media {
+class AudioManager;
+
+namespace mojom {
+class AudioOutputService;
+}  //  namespace mojom
+}  //  namespace media
+
+namespace content {
+
+class AudioMirroringManager;
+class AudioOutputServiceImpl;
+class MediaStreamManager;
+
+class CONTENT_EXPORT AudioOutputServiceContext {
+ public:
+  AudioOutputServiceContext(int render_process_id,
+                            media::AudioManager* audio_manager,
+                            MediaStreamManager* media_stream_manager,
+                            AudioMirroringManager* mirroring_manager,
+                            const std::string& salt);
+  ~AudioOutputServiceContext();
+
+  void CreateService(
+      int frame_host_id,
+      mojo::InterfaceRequest<media::mojom::AudioOutputService> request);
+
+  void ServiceHadConnectionError(AudioOutputServiceImpl* service);
+
+  // Accessors for data common to all AudioOutputServiceImpls for a single
+  // render process.
+  int render_process_id() const { return render_process_id_; }
+
+  const AudioOutputAuthorizationHandler* authorization_handler() const {
+    return &authorization_handler_;
+  }
+
+  const std::string& salt() const { return salt_; }
+
+  AudioOutputDelegate::UniquePtr CreateDelegate(
+      const std::string& unique_device_id,
+      int render_frame_id,
+      AudioOutputDelegate::EventHandler* handler,
+      const media::AudioParameters& params);
+
+ private:
+  const int render_process_id_;
+  media::AudioManager* const audio_manager_;

[o1ka, 2017/01/25 15:15:21]

It would be great to avoid duplications between AudioRendererHost and Mojo
version of the code.

+  MediaStreamManager* const media_stream_manager_;
+  AudioMirroringManager* const mirroring_manager_;
+  const std::string salt_;
+  AudioOutputAuthorizationHandler authorization_handler_;
+  int next_stream_id_ = 0;
+
+  std::vector<std::unique_ptr<AudioOutputServiceImpl>> services_;

[o1ka, 2017/01/25 15:15:21]

Can't you manage it with StrongBindingSet instead?
(https://cs.chromium.org/chromium/src/media/mojo/services/strong_binding_set.h...)
It will do all the lifetime management for us.

+};
+
+}  // namespace content
+
+#endif  //  CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_OUTPUT_SERVICE_CONTEXT_H_