If user profile doesn't contain language setting, default to his Google account settings.

chrome/browser/profiles/profile_impl.cc

 // Copyright (c) 2012 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/profiles/profile_impl.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
@@ skipping 11 matching lines @@
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/version.h"
 #include "chrome/browser/autocomplete/autocomplete_classifier.h"
 #include "chrome/browser/background/background_contents_service_factory.h"
 #include "chrome/browser/background/background_mode_manager.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/chromeos/login/language_switch_menu.h"
 #include "chrome/browser/content_settings/cookie_settings.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/download/chrome_download_manager_delegate.h"
 #include "chrome/browser/download/download_service.h"
 #include "chrome/browser/download/download_service_factory.h"
 #include "chrome/browser/extensions/extension_pref_store.h"
 #include "chrome/browser/extensions/extension_pref_value_map.h"
 #include "chrome/browser/extensions/extension_pref_value_map_factory.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_special_storage_policy.h"
@@ skipping 93 matching lines @@
 // Make sure that the ProfileImpl doesn't grow. We're currently trying to drive
 // the number of services that are included in ProfileImpl (instead of using
 // BrowserContextKeyedServiceFactory) to zero.
 //
 // If you don't know about this effort, please read:
 //   https://sites.google.com/a/chromium.org/dev/developers/design-documents/profile-architecture
 //
 // REVIEWERS: Do not let anyone increment this. We need to drive the number of
 // raw accessed services down to zero. DO NOT LET PEOPLE REGRESS THIS UNLESS
 // THE PATCH ITSELF IS MAKING PROGRESS ON PKSF REFACTORING.
 COMPILE_ASSERT(sizeof(ProfileImpl) <= 744u, profile_impl_size_unexpected);

[sail, 2013/08/23 17:08:48]

Your CL will probably break this assert.
Could you move this into a separate class or into another existing class?

[Alexander Alekseev, 2013/09/06 19:52:08]

Done.

 #endif
 
 #if defined(ENABLE_SESSION_SERVICE)
 // Delay, in milliseconds, before we explicitly create the SessionService.
 static const int kCreateSessionServiceDelayMS = 500;
 #endif
 
 // Text content of README file created in each profile directory. Both %s
 // placeholders must contain the product name. This is not localizable and hence
 // not in resources.
@@ skipping 198 matching lines @@
     CreateMode create_mode,
     base::SequencedTaskRunner* sequenced_task_runner)
     : zoom_callback_(base::Bind(&ProfileImpl::OnZoomLevelChanged,
                                 base::Unretained(this))),
       path_(path),
       pref_registry_(new user_prefs::PrefRegistrySyncable),
       io_data_(this),
       host_content_settings_map_(NULL),
       last_session_exit_type_(EXIT_NORMAL),
       start_time_(Time::Now()),
+#if defined(OS_CHROMEOS)
+      is_created_(false),
+#endif
       delegate_(delegate),
       predictor_(NULL) {
   TRACE_EVENT0("browser", "ProfileImpl::ctor")
   DCHECK(!path.empty()) << "Using an empty path will attempt to write " <<
                             "profile files to the root directory!";
 
 #if defined(ENABLE_SESSION_SERVICE)
   create_session_service_timer_.Start(FROM_HERE,
       TimeDelta::FromMilliseconds(kCreateSessionServiceDelayMS), this,
       &ProfileImpl::EnsureSessionServiceCreated);
@@ skipping 606 matching lines @@
 void ProfileImpl::StopCreateSessionServiceTimer() {
   create_session_service_timer_.Stop();
 }
 
 void ProfileImpl::EnsureSessionServiceCreated() {
   SessionServiceFactory::GetForProfile(this);
 }
 #endif
 
 #if defined(OS_CHROMEOS)
+void ProfileImpl::MarkCreated() {
+  is_created_ = true;
+}
+
 void ProfileImpl::ChangeAppLocale(
     const std::string& new_locale, AppLocaleChangedVia via) {
   if (new_locale.empty()) {
     NOTREACHED();
     return;
   }
   PrefService* local_state = g_browser_process->local_state();
   DCHECK(local_state);
   if (local_state->IsManagedPreference(prefs::kApplicationLocale))
     return;
@@ skipping 35 matching lines @@
       } else {
         std::string cur_locale = g_browser_process->GetApplicationLocale();
         std::string backup_locale =
             GetPrefs()->GetString(prefs::kApplicationLocaleBackup);
         // Profile synchronization takes time and is not completed at that
         // moment at first login.  So we initialize locale preference in steps:
         // (1) first save it to temporary backup;
         // (2) on next login we assume that synchronization is already completed
         //     and we may finalize initialization.
         GetPrefs()->SetString(prefs::kApplicationLocaleBackup, cur_locale);
-        if (!backup_locale.empty())
+        if (!new_locale.empty())
+          GetPrefs()->SetString(prefs::kApplicationLocale, new_locale);
+        else if (!backup_locale.empty())
           GetPrefs()->SetString(prefs::kApplicationLocale, backup_locale);
         do_update_pref = false;
       }
       break;
     }
     case APP_LOCALE_CHANGED_VIA_UNKNOWN:
     default: {
       NOTREACHED();
       break;
     }
   }
   if (do_update_pref)
     GetPrefs()->SetString(prefs::kApplicationLocale, new_locale);
   local_state->SetString(prefs::kApplicationLocale, new_locale);
 
   if (chromeos::UserManager::Get()->IsCurrentUserOwner())
     local_state->SetString(prefs::kOwnerLocale, new_locale);
 }
 
+void ProfileImpl::SetGPlusProfileLocale(const std::string& gplus_locale) {
+  gplus_locale_.reset(new std::string);
+  // Ignore result
+  l10n_util::CheckAndResolveLocale(gplus_locale, gplus_locale_.get());

[jungshik at Google, 2013/08/26 16:42:50]

This does not take into account the preferred language list in the Google user
profile. If a user's primary language is not supported by Chrome OS (let's say,
"Foo") but one of languages in the fallback list in the user's Google profile
(e.g. French) is supported by Chrome, we have to pick it up instead of falling
back to the universal (hard-coded) fallback ('en-US'). 

The Linux locale fallback has a similar mechanism because 'LANGUAGE' environment
variable can have a list of languages (e.g. 'foo:fr-CA:fr-FR').  

If you don't want to do now, at least add TODO comment about this. 

[Alexander Alekseev, 2013/09/06 19:52:08]

I like the idea, but I couldn't find "list of languages" in API.
https://developers.google.com/+/api/latest/people
- doesn't list anything alike.

[jungshik at Google, 2013/09/18 08:50:04]

Thanks for digging that up. I've alerted an engineer working on the language
setting of Google users. He's not aware of this API.

+  RespectLocalePreference();
+}
+
+void ProfileImpl::RespectLocalePreference() {
+  PrefService* prefs = GetPrefs();
+  DCHECK(prefs != NULL);
+  if (g_browser_process == NULL)
+    return;
+
+  if (!is_created_)
+    return;
+
+  if (gplus_locale_ == NULL)
+    return;
+
+  std::string pref_locale = prefs->GetString(prefs::kApplicationLocale);
+  if (pref_locale.empty())
+    pref_locale = prefs->GetString(prefs::kApplicationLocaleBackup);
+  if (pref_locale.empty())
+    pref_locale = *gplus_locale_;
+  if (pref_locale.empty())
+    pref_locale = g_browser_process->GetApplicationLocale();
+  DCHECK(!pref_locale.empty());
+  ChangeAppLocale(pref_locale, APP_LOCALE_CHANGED_VIA_LOGIN);
+  // Here we don't enable keyboard layouts. Input methods are set up when
+  // the user first logs in. Then the user may customize the input methods.
+  // Hence changing input methods here, just because the user's UI language
+  // is different from the login screen UI language, is not desirable. Note
+  // that input method preferences are synced, so users can use their
+  // farovite input methods as soon as the preferences are synced.
+  chromeos::LanguageSwitchMenu::SwitchLanguage(pref_locale);
+}
+
 void ProfileImpl::OnLogin() {
   if (locale_change_guard_ == NULL)
     locale_change_guard_.reset(new chromeos::LocaleChangeGuard(this));
   locale_change_guard_->OnLogin();
 }
 
 void ProfileImpl::SetupChromeOSEnterpriseExtensionObserver() {
   DCHECK(!chromeos_enterprise_extension_observer_);
   chromeos_enterprise_extension_observer_.reset(
       new chromeos::EnterpriseExtensionObserver(this));
@@ skipping 100 matching lines @@
 PrefProxyConfigTracker* ProfileImpl::CreateProxyConfigTracker() {
 #if defined(OS_CHROMEOS)
   if (chromeos::ProfileHelper::IsSigninProfile(this)) {
     return ProxyServiceFactory::CreatePrefProxyConfigTrackerOfLocalState(
         g_browser_process->local_state());
   }
 #endif  // defined(OS_CHROMEOS)
   return ProxyServiceFactory::CreatePrefProxyConfigTrackerOfProfile(
       GetPrefs(), g_browser_process->local_state());
 }