Make "source" a required argument of AppLaunchParams and fill in the argument in all call points.

chrome/browser/chromeos/login/demo_mode/demo_app_launcher.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 "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "chrome/browser/chromeos/app_mode/app_session_lifetime.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/extensions/app_launch_params.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/grit/browser_resources.h"
 #include "chromeos/network/network_handler.h"
 #include "chromeos/network/network_state_handler.h"
 #include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
+#include "extensions/common/constants.h"
 #include "extensions/common/extension.h"
 #include "ui/base/window_open_disposition.h"
 
 namespace chromeos {
 
 const char DemoAppLauncher::kDemoUserName[] = "demouser@demo.app.local";
 const char DemoAppLauncher::kDemoAppId[] = "klimoghijjogocdbaikffefjfcfheiel";
 const base::FilePath::CharType kDefaultDemoAppPath[] =
     FILE_PATH_LITERAL("/usr/share/chromeos-assets/demo_app");
 
@@ skipping 50 matching lines @@
     return;
   }
 
   // Disable network before launching the app.
   LOG(WARNING) << "Disabling network before launching demo app..";
   NetworkStateHandler* handler = NetworkHandler::Get()->network_state_handler();
   handler->SetTechnologyEnabled(NetworkTypePattern::NonVirtual(),
                                 false,
                                 chromeos::network_handler::ErrorCallback());
 
-  OpenApplication(AppLaunchParams(
-      profile, extension, extensions::LAUNCH_CONTAINER_WINDOW, NEW_WINDOW));
+  OpenApplication(
+      AppLaunchParams(profile, extension, extensions::LAUNCH_CONTAINER_WINDOW,
+                      NEW_WINDOW, extensions::SOURCE_CHROME_INTERNAL));
   InitAppSession(profile, extension_id);
 
   user_manager::UserManager::Get()->SessionStarted();
 
   LoginDisplayHostImpl::default_host()->Finalize();
 }
 
 void DemoAppLauncher::OnProfileLoadFailed(KioskAppLaunchError::Error error) {
   LOG(ERROR) << "Loading the Kiosk Profile failed: " <<
       KioskAppLaunchError::GetErrorMessage(error);
 }
 
 }  // namespace chromeos