PPAPI: Add an API for setting a custom user agent for URL requests.

ppapi/proxy/ppapi_messages.h

 // 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.
 
 // Multiply-included message header, no traditional include guard.
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
@@ skipping 195 matching lines @@
   IPC_STRUCT_TRAITS_MEMBER(record_download_progress)
   IPC_STRUCT_TRAITS_MEMBER(record_upload_progress)
   IPC_STRUCT_TRAITS_MEMBER(has_custom_referrer_url)
   IPC_STRUCT_TRAITS_MEMBER(custom_referrer_url)
   IPC_STRUCT_TRAITS_MEMBER(allow_cross_origin_requests)
   IPC_STRUCT_TRAITS_MEMBER(allow_credentials)
   IPC_STRUCT_TRAITS_MEMBER(has_custom_content_transfer_encoding)
   IPC_STRUCT_TRAITS_MEMBER(custom_content_transfer_encoding)
   IPC_STRUCT_TRAITS_MEMBER(prefetch_buffer_upper_threshold)
   IPC_STRUCT_TRAITS_MEMBER(prefetch_buffer_lower_threshold)
+  IPC_STRUCT_TRAITS_MEMBER(has_custom_user_agent)
+  IPC_STRUCT_TRAITS_MEMBER(custom_user_agent)
   IPC_STRUCT_TRAITS_MEMBER(body)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(ppapi::PPB_URLRequestInfo_Data::BodyItem)
   IPC_STRUCT_TRAITS_MEMBER(is_file)
   IPC_STRUCT_TRAITS_MEMBER(data)
   // Note: we don't serialize file_ref.
   IPC_STRUCT_TRAITS_MEMBER(file_ref_host_resource)
   IPC_STRUCT_TRAITS_MEMBER(start_offset)
   IPC_STRUCT_TRAITS_MEMBER(number_of_bytes)
@@ skipping 1207 matching lines @@
                      ppapi::proxy::ResourceMessageCallParams /* call_params */,
                      IPC::Message /* nested_msg */)
 
 // A resource reply is a response to a ResourceCall from a host to the
 // plugin. The resource ID + sequence number in the params will correspond to
 // that of the previous ResourceCall.
 IPC_MESSAGE_CONTROL2(
     PpapiPluginMsg_ResourceReply,
     ppapi::proxy::ResourceMessageReplyParams /* reply_params */,
     IPC::Message /* nested_msg */)