Make platform apps use and require a different container ("shell" instead of "panel")

chrome/browser/extensions/extension_prefs.cc

 // Copyright (c) 2011 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_prefs.h"
 
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_pref_store.h"
@@ skipping 955 matching lines @@
     const Extension* extension,
     ExtensionPrefs::LaunchType default_pref_value) {
   extension_misc::LaunchContainer manifest_launch_container =
       extension->launch_container();
 
   const extension_misc::LaunchContainer kInvalidLaunchContainer =
       static_cast<extension_misc::LaunchContainer>(-1);
 
   extension_misc::LaunchContainer result = kInvalidLaunchContainer;
 
-  if (manifest_launch_container == extension_misc::LAUNCH_PANEL) {
-    // Apps with app.launch.container = 'panel' should always
-    // open in a panel.
-    result = extension_misc::LAUNCH_PANEL;
+  if (manifest_launch_container == extension_misc::LAUNCH_PANEL ||
+      manifest_launch_container == extension_misc::LAUNCH_SHELL) {
+    // Apps with app.launch.container = 'panel' or 'shell' should always respect
+    // the manifest setting.
+    result = manifest_launch_container;
 
   } else if (manifest_launch_container == extension_misc::LAUNCH_TAB) {
     // Look for prefs that indicate the user's choice of launch
     // container.  The app's menu on the NTP provides a UI to set
     // this preference.  If no preference is set, |default_pref_value|
     // is used.
     ExtensionPrefs::LaunchType prefs_launch_type =
         GetLaunchType(extension->id(), default_pref_value);
 
     if (prefs_launch_type == ExtensionPrefs::LAUNCH_WINDOW) {
@@ skipping 832 matching lines @@
   prefs->RegisterListPref(prefs::kExtensionInstallAllowList,
                           PrefService::UNSYNCABLE_PREF);
   prefs->RegisterListPref(prefs::kExtensionInstallDenyList,
                           PrefService::UNSYNCABLE_PREF);
   prefs->RegisterListPref(prefs::kExtensionInstallForceList,
                           PrefService::UNSYNCABLE_PREF);
   prefs->RegisterStringPref(kWebStoreLogin,
                             std::string() /* default_value */,
                             PrefService::UNSYNCABLE_PREF);
 }