Support multiple files for AEC dump.

content/common/media/aec_dump_messages.h

+// Copyright 2014 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.
+
+// IPC messages for the AEC dump.
+// Multiply-included message file, hence no include guard.
+
+#include "content/common/content_export.h"
+#include "ipc/ipc_message_macros.h"
+#include "ipc/ipc_platform_file.h"
+
+#undef IPC_MESSAGE_EXPORT
+#define IPC_MESSAGE_EXPORT CONTENT_EXPORT
+#define IPC_MESSAGE_START AecDumpMsgStart
+
+// Messages sent from the browser to the renderer.
+
+// The browser hands over a file handle to the consumer in the renderer
+// identified by |id| to use for AEC dump.
+IPC_MESSAGE_CONTROL2(AecDumpMsg_EnableAecDump,
+                     int /* id */,
+                     IPC::PlatformFileForTransit /* file_handle */)
+
+// Tell the renderer to disable AEC dump in all consumers.
+IPC_MESSAGE_CONTROL0(AecDumpMsg_DisableAecDump)
+
+// Messages sent from the renderer to the browser.
+
+// Registers a consumer with the browser. The consumer will then get a file
+// handle when the dump is enabled.
+IPC_MESSAGE_CONTROL1(AecDumpMsg_RegisterAecDumpConsumer,
+                     int /* id */)
+
+// Unregisters a consumer with the browser.
+IPC_MESSAGE_CONTROL1(AecDumpMsg_UnregisterAecDumpConsumer,
+                     int /* id */)