ipc: Make a new class PlaceholderBrokerableAttachment.

ipc/attachment_broker_privileged_win.cc

 // Copyright 2015 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 "ipc/attachment_broker_privileged_win.h"
 
 #include <windows.h>
 
 #include "base/process/process.h"
 #include "ipc/attachment_broker_messages.h"
 #include "ipc/brokerable_attachment.h"
 #include "ipc/handle_attachment_win.h"
 #include "ipc/ipc_channel.h"
 
 namespace IPC {
 
 AttachmentBrokerPrivilegedWin::AttachmentBrokerPrivilegedWin() {}
 
 AttachmentBrokerPrivilegedWin::~AttachmentBrokerPrivilegedWin() {}
 
 bool AttachmentBrokerPrivilegedWin::SendAttachmentToProcess(
     const BrokerableAttachment* attachment,
     base::ProcessId destination_process) {
   switch (attachment->GetBrokerableType()) {
-    case BrokerableAttachment::WIN_HANDLE:
+    case BrokerableAttachment::WIN_HANDLE: {
       const internal::HandleAttachmentWin* handle_attachment =
           static_cast<const internal::HandleAttachmentWin*>(attachment);
       HandleWireFormat wire_format =
           handle_attachment->GetWireFormat(destination_process);
       HandleWireFormat new_wire_format =
           DuplicateWinHandle(wire_format, base::Process::Current().Pid());
       if (new_wire_format.handle == 0)
         return false;
       RouteDuplicatedHandle(new_wire_format);
       return true;
+    }
+    case BrokerableAttachment::PLACEHOLDER:
+      NOTREACHED();
+      return false;
   }
   return false;
 }
 
 bool AttachmentBrokerPrivilegedWin::OnMessageReceived(const Message& msg) {
   bool handled = true;
   switch (msg.type()) {
     IPC_MESSAGE_HANDLER_GENERIC(AttachmentBrokerMsg_DuplicateWinHandle,
                                 OnDuplicateWinHandle(msg))
     IPC_MESSAGE_UNHANDLED(handled = false)
@@ skipping 78 matching lines @@
                                      dest_process.Handle(), &new_handle,
                                      desired_access, FALSE, options);
 
     new_wire_format.handle = (result != 0) ? HandleToLong(new_handle) : 0;
   }
 
   return new_wire_format;
 }
 
 }  // namespace IPC