Alter the design of the bootstrap sandbox to only take over the bootstrap port of children when nec…

sandbox/mac/mach_message_server.h

Index: sandbox/mac/mach_message_server.h
diff --git a/sandbox/mac/mach_message_server.h b/sandbox/mac/mach_message_server.h
index f37b4fcebfa4276f7262943ab03a835355113049..5c05c39b41477aa254dbcde989dce909ae4f4b75 100644
--- a/sandbox/mac/mach_message_server.h
+++ b/sandbox/mac/mach_message_server.h
@@ -33,7 +33,14 @@ class MessageDemuxer {
 // different port, or reply to the message with a MIG error.
 class MachMessageServer {
  public:
-  MachMessageServer(MessageDemuxer* demuxer, mach_msg_size_t buffer_size);
+  // Creates a new Mach message server that will send messages to |demuxer|
+  // for handling. If the |server_receive_right| is non-NULL, this class will
+  // take ownership of the port and it will be used to receive messages.
+  // Otherwise the server will create a new receive right.
+  // The maximum size of messages is specified by |buffer_size|.
+  MachMessageServer(MessageDemuxer* demuxer,
+                    mach_port_t server_receive_right,
+                    mach_msg_size_t buffer_size);
   ~MachMessageServer();
 
   // Initializes the class and starts running the message server. If this