Revert of ash: Use system tray mojo interface to show system update tray icon

ash/common/test/test_system_tray_delegate.cc

 // Copyright 2013 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 "ash/common/test/test_system_tray_delegate.h"
 
 #include <string>
 
 #include "ash/common/login_status.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/wm_shell.h"
 #include "base/time/time.h"
 
 namespace ash {
 namespace test {
 
 namespace {
 
+bool g_system_update_required = false;
 LoginStatus g_initial_status = LoginStatus::USER;
 
 }  // namespace
 
 TestSystemTrayDelegate::TestSystemTrayDelegate()
     : login_status_(g_initial_status), session_length_limit_set_(false) {}
 
 TestSystemTrayDelegate::~TestSystemTrayDelegate() {}
 
 void TestSystemTrayDelegate::SetLoginStatus(LoginStatus login_status) {
@@ skipping 34 matching lines @@
     return LoginStatus::NOT_LOGGED_IN;
   if (delegate->IsScreenLocked())
     return LoginStatus::LOCKED;
   return login_status_;
 }
 
 bool TestSystemTrayDelegate::IsUserSupervised() const {
   return login_status_ == LoginStatus::SUPERVISED;
 }
 
+void TestSystemTrayDelegate::GetSystemUpdateInfo(UpdateInfo* info) const {
+  DCHECK(info);
+  info->severity = UpdateInfo::UPDATE_NONE;
+  info->update_required = g_system_update_required;
+  info->factory_reset_required = false;
+}
+
 bool TestSystemTrayDelegate::GetSessionStartTime(
     base::TimeTicks* session_start_time) {
   // Just returns TimeTicks::Now(), so the remaining time is always the
   // specified limit. This is useful for testing.
   if (session_length_limit_set_)
     *session_start_time = base::TimeTicks::Now();
   return session_length_limit_set_;
 }
 
 bool TestSystemTrayDelegate::GetSessionLengthLimit(
@@ skipping 17 matching lines @@
     : old_status_(g_initial_status) {
   g_initial_status = new_status;
 }
 
 ScopedInitialLoginStatus::~ScopedInitialLoginStatus() {
   g_initial_status = old_status_;
 }
 
 }  // namespace test
 }  // namespace ash