Enable login screen apps.

chrome/browser/extensions/extension_system_impl.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/extensions/extension_system_impl.h"
 
 #include <algorithm>
 
 #include "apps/app_restore_service.h"
 #include "apps/app_restore_service_factory.h"
@@ skipping 191 matching lines @@
   service_worker_manager_.reset(new ServiceWorkerManager(profile_));
 
   shared_user_script_master_.reset(new SharedUserScriptMaster(profile_));
 
   // ExtensionService depends on RuntimeData.
   runtime_data_.reset(new RuntimeData(ExtensionRegistry::Get(profile_)));
 
   bool autoupdate_enabled = !profile_->IsGuestSession() &&
                             !profile_->IsSystemProfile();
 #if defined(OS_CHROMEOS)
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableLoginScreenApps) &&
+      chromeos::ProfileHelper::IsSigninProfile(profile_)) {
+    extensions_enabled = true;

[Devlin, 2017/03/08 17:24:32]

I'd rather we instead update the call site to pass the proper value for
extensions_enabled here - it's confusing to have multiple places determine it.

[achuithb, 2017/03/09 14:31:05]

Done.

+  }
   if (!extensions_enabled)
     autoupdate_enabled = false;
 #endif  // defined(OS_CHROMEOS)
   extension_service_.reset(new ExtensionService(
       profile_, base::CommandLine::ForCurrentProcess(),
       profile_->GetPath().AppendASCII(extensions::kInstallDirectoryName),
       ExtensionPrefs::Get(profile_), Blacklist::Get(profile_),
       autoupdate_enabled, extensions_enabled, &ready_));
 
   uninstall_ping_sender_.reset(new UninstallPingSender(
@@ skipping 241 matching lines @@
 void ExtensionSystemImpl::UnregisterExtensionWithRequestContexts(
     const std::string& extension_id,
     const UnloadedExtensionInfo::Reason reason) {
   BrowserThread::PostTask(
       BrowserThread::IO,
       FROM_HERE,
       base::Bind(&InfoMap::RemoveExtension, info_map(), extension_id, reason));
 }
 
 }  // namespace extensions