Change userid from a uint32_t to a string guid

mash/browser_driver/browser_driver_application_delegate.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 "mash/browser_driver/browser_driver_application_delegate.h"
 
 #include <stdint.h>
 
 #include "base/bind.h"
 #include "components/mus/public/cpp/event_matcher.h"
@@ skipping 34 matching lines @@
 }  // namespace
 
 BrowserDriverApplicationDelegate::BrowserDriverApplicationDelegate()
     : connector_(nullptr),
       binding_(this) {}
 
 BrowserDriverApplicationDelegate::~BrowserDriverApplicationDelegate() {}
 
 void BrowserDriverApplicationDelegate::Initialize(mojo::Connector* connector,
                                                   const std::string& url,
-                                                  uint32_t id,
-                                                  uint32_t user_id) {
+                                                  const std::string& user_id,
+                                                  uint32_t id) {
   connector_ = connector;
   AddAccelerators();
 }
 
 bool BrowserDriverApplicationDelegate::AcceptConnection(
     mojo::Connection* connection) {
   return true;
 }
 
 void BrowserDriverApplicationDelegate::OnAccelerator(
@@ skipping 30 matching lines @@
   for (const AcceleratorSpec& spec : g_spec) {
     registrar->AddAccelerator(
         static_cast<uint32_t>(spec.id),
         mus::CreateKeyMatcher(spec.keyboard_code, spec.event_flags),
         base::Bind(&AssertTrue));
   }
 }
 
 }  // namespace browser_driver
 }  // namespace main