Do not assign launch ordinals to ephemeral apps

chrome/browser/extensions/chrome_app_sorting.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 "chrome/browser/extensions/chrome_app_sorting.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/extensions/extension_sync_service.h"
+#include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "content/public/browser/notification_service.h"
 #include "extensions/browser/extension_scoped_prefs.h"
+#include "extensions/browser/extension_util.h"
 #include "extensions/common/extension.h"
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/extensions/default_app_order.h"
 #endif
 
 namespace extensions {
 
 namespace {
 
@@ skipping 15 matching lines @@
 // ChromeAppSorting::AppOrdinals
 
 ChromeAppSorting::AppOrdinals::AppOrdinals() {}
 
 ChromeAppSorting::AppOrdinals::~AppOrdinals() {}
 
 ////////////////////////////////////////////////////////////////////////////////
 // ChromeAppSorting
 
 ChromeAppSorting::ChromeAppSorting()
-    : extension_scoped_prefs_(NULL),
+    : profile_(NULL),
+      extension_scoped_prefs_(NULL),
       extension_sync_service_(NULL),
       default_ordinals_created_(false) {
 }
 
 ChromeAppSorting::~ChromeAppSorting() {
 }
 
 void ChromeAppSorting::SetExtensionScopedPrefs(ExtensionScopedPrefs* prefs) {
   extension_scoped_prefs_ = prefs;
 }
 
 void ChromeAppSorting::SetExtensionSyncService(
     ExtensionSyncService* extension_sync_service) {
   extension_sync_service_ = extension_sync_service;
+  profile_ = extension_sync_service->profile();
 }
 
 void ChromeAppSorting::Initialize(
     const extensions::ExtensionIdList& extension_ids) {
   InitializePageOrdinalMap(extension_ids);
 
   MigrateAppIndex(extension_ids);
 }
 
 void ChromeAppSorting::CreateOrdinalsIfNecessary(size_t minimum_size) {
@@ skipping 144 matching lines @@
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_EXTENSION_LAUNCHER_REORDERED,
       content::Source<ChromeAppSorting>(this),
       content::NotificationService::NoDetails());
 }
 
 void ChromeAppSorting::EnsureValidOrdinals(
     const std::string& extension_id,
     const syncer::StringOrdinal& suggested_page) {
+  // Although installed transiently, ephemeral apps are not visible in the UI.
+  if (profile_ && util::IsEphemeralApp(extension_id, profile_))
+    return;

[tapted, 2014/07/16 05:03:38]

It might not be safe to return early from here

"things" (e.g. chrome/browser/ui/app_list/extension_app_item.cc) can currently
assume an ordinal is set after calling this, which guarantees that the ordinal
can be fetched and compared with another ordinal without hitting any of the
CHECK(..)s in ordinal.h

There might be some more context about this failures in http://crbug.com/167752 
(or searching for closed bugs that mention 'EnsureValidOrdinals')

+
   syncer::StringOrdinal page_ordinal = GetPageOrdinal(extension_id);
   if (!page_ordinal.IsValid()) {
     if (suggested_page.IsValid()) {
       page_ordinal = suggested_page;
     } else if (!GetDefaultOrdinals(extension_id, &page_ordinal, NULL) ||
         !page_ordinal.IsValid()) {
       page_ordinal = GetNaturalAppPageOrdinal();
     }
 
     SetPageOrdinal(extension_id, page_ordinal);
@@ skipping 375 matching lines @@
   for (AppLaunchOrdinalMap::const_iterator it = m.begin(); it != m.end();
        ++it) {
     const std::string& id = it->second;
     if (ntp_hidden_extensions_.count(id) == 0)
       result++;
   }
   return result;
 }
 
 }  // namespace extensions