Revert of Quit the message loop by default in ShellConnectionLost when ApplicationRunner is used

mojo/shell/public/cpp/lib/shell_connection.cc

 // 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.
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "mojo/public/cpp/bindings/interface_ptr.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "mojo/shell/public/cpp/capabilities.h"
@@ skipping 68 matching lines @@
   incoming_connections_.push_back(std::move(registry));
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ShellConnection, private:
 
 void ShellConnection::OnConnectionError() {
   // Note that the ShellClient doesn't technically have to quit now, it may live
   // on to service existing connections. All existing Connectors however are
   // invalid.
-  if (client_->ShellConnectionLost() && !connection_lost_closure_.is_null())
-    connection_lost_closure_.Run();
+  client_->ShellConnectionLost();
   // We don't reset the connector as clients may have taken a raw pointer to it.
   // Connect() will return nullptr if they try to connect to anything.
 }
 
 }  // namespace mojo