Introduce PPB_AudioInput_Dev v0.3 and refactor the device enumeration code:

ppapi/proxy/device_enumeration_resource_helper.h

Index: ppapi/proxy/device_enumeration_resource_helper.h
diff --git a/ppapi/proxy/device_enumeration_resource_helper.h b/ppapi/proxy/device_enumeration_resource_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..744a0ebe7693a40d8dc9df75e084aaba6c9151d8
--- /dev/null
+++ b/ppapi/proxy/device_enumeration_resource_helper.h
@@ -0,0 +1,82 @@
+// Copyright (c) 2012 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 PPAPI_PROXY_DEVICE_ENUMERATION_RESOURCE_HELPER_H_
+#define PPAPI_PROXY_DEVICE_ENUMERATION_RESOURCE_HELPER_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "ppapi/c/dev/ppb_device_ref_dev.h"
+#include "ppapi/proxy/ppapi_proxy_export.h"
+
+namespace IPC {
+class Message;
+}
+
+struct PP_ArrayOutput;
+
+namespace ppapi {
+
+struct DeviceRefData;
+class TrackedCallback;
+
+namespace proxy {
+
+class PluginResource;
+class ResourceMessageReplyParams;
+
+class PPAPI_PROXY_EXPORT DeviceEnumerationResourceHelper
+    : public base::SupportsWeakPtr<DeviceEnumerationResourceHelper> {
+ public:
+  // |owner| must outlive this object.
+  explicit DeviceEnumerationResourceHelper(PluginResource* owner);
+  ~DeviceEnumerationResourceHelper();
+
+  int32_t EnumerateDevices0_2(PP_Resource* devices,
+                              scoped_refptr<TrackedCallback> callback);
+  int32_t EnumerateDevices(const PP_ArrayOutput& output,
+                           scoped_refptr<TrackedCallback> callback);
+  int32_t MonitorDeviceChange(PP_MonitorDeviceChangeCallback callback,
+                              void* user_data);
+
+  // Returns true if the message has been handled.
+  bool HandleReply(const ResourceMessageReplyParams& params,
+                   const IPC::Message& msg);
+
+  void LastPluginRefWasDeleted();
+
+ private:
+  void OnPluginMsgEnumerateDevicesReply0_2(
+      PP_Resource* devices_resource,
+      scoped_refptr<TrackedCallback> callback,
+      const ResourceMessageReplyParams& params,
+      const std::vector<DeviceRefData>& devices);
+  void OnPluginMsgEnumerateDevicesReply(
+      const PP_ArrayOutput& output,
+      scoped_refptr<TrackedCallback> callback,
+      const ResourceMessageReplyParams& params,
+      const std::vector<DeviceRefData>& devices);
+  void OnPluginMsgNotifyDeviceChange(const ResourceMessageReplyParams& params,
+                                     uint32_t callback_id,
+                                     const std::vector<DeviceRefData>& devices);
+
+  // Not owned by this object.
+  PluginResource* owner_;
+
+  bool pending_enumerate_devices_;
+
+  uint32_t monitor_callback_id_;
+  PP_MonitorDeviceChangeCallback monitor_callback_;
+  void* monitor_user_data_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceEnumerationResourceHelper);
+};
+
+}  // namespace proxy
+}  // namespace ppapi
+
+#endif  // PPAPI_PROXY_DEVICE_ENUMERATION_RESOURCE_HELPER_H_