Attempt to recover sync token for managed user once we detected that sync auth fails.

chrome/browser/chromeos/login/supervised_user_manager_impl.cc

Index: chrome/browser/chromeos/login/supervised_user_manager_impl.cc
diff --git a/chrome/browser/chromeos/login/supervised_user_manager_impl.cc b/chrome/browser/chromeos/login/supervised_user_manager_impl.cc
index 15132ea3abba57ed8935ec44f18b2832be45d01a..2c86e238359107494c74ce802ce3101e73ef0cfa 100644
--- a/chrome/browser/chromeos/login/supervised_user_manager_impl.cc
+++ b/chrome/browser/chromeos/login/supervised_user_manager_impl.cc
@@ -4,16 +4,23 @@
 
 #include "chrome/browser/chromeos/login/supervised_user_manager_impl.h"
 
+#include "base/file_util.h"
+#include "base/files/file_path.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chromeos/login/managed/locally_managed_user_constants.h"
 #include "chrome/browser/chromeos/login/managed/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/user_manager_impl.h"
+#include "chrome/browser/chromeos/profiles/profile_helper.h"
+#include "chrome/browser/managed_mode/managed_user_service.h"
+#include "chrome/browser/managed_mode/managed_user_service_factory.h"
 #include "chromeos/settings/cros_settings_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "google_apis/gaia/gaia_auth_util.h"
@@ -67,6 +74,16 @@ const char kSupervisedUserPasswordSalt[] =
 const char kSupervisedUserPasswordRevision[] =
     "SupervisedUserPasswordRevision";
 
+std::string LoadSyncToken(base::FilePath profile_dir) {
+  std::string token;
+  base::FilePath token_file =
+      profile_dir.Append(chromeos::kManagedUserTokenFilename);
+  VLOG(1) << "Loading" << token_file.value();
+  if (!base::ReadFileToString(token_file, &token))
+    return std::string();
+  return token;
+}
+
 } // namespace
 
 namespace chromeos {
@@ -417,4 +434,24 @@ SupervisedUserAuthentication* SupervisedUserManagerImpl::GetAuthentication() {
   return authentication_.get();
 }
 
+void SupervisedUserManagerImpl::LoadSupervisedUserToken(
+    Profile* profile,
+    const LoadTokenCallback& callback) {
+  // TODO(antrim): use profile->GetPath() once we sure it is safe.
+  base::FilePath profile_dir = ProfileHelper::GetProfilePathByUserIdHash(
+      UserManager::Get()->GetUserByProfile(profile)->username_hash());
+  PostTaskAndReplyWithResult(
+      content::BrowserThread::GetBlockingPool(),
+      FROM_HERE,
+      base::Bind(&LoadSyncToken, profile_dir),
+      callback);
+}
+
+void SupervisedUserManagerImpl::ConfigureSyncWithToken(
+    Profile* profile,
+    const std::string& token) {
+  if (!token.empty())
+    ManagedUserServiceFactory::GetForProfile(profile)->InitSync(token);
+}
+
 }  // namespace chromeos