Fix refresh token is not available after Chrome restart on crash.

components/signin/core/browser/signin_manager_base.cc

Index: components/signin/core/browser/signin_manager_base.cc
diff --git a/components/signin/core/browser/signin_manager_base.cc b/components/signin/core/browser/signin_manager_base.cc
index 68d68b477b4334edc4d004773f9daa798cc5621d..d0e55b7c61fdf433a87406cb5c7d57c9c91c1be3 100644
--- a/components/signin/core/browser/signin_manager_base.cc
+++ b/components/signin/core/browser/signin_manager_base.cc
@@ -216,6 +216,8 @@ void SigninManagerBase::SetAuthenticatedAccountId(
                                  account_id);
   client_->GetPrefs()->SetString(prefs::kGoogleServicesLastUsername,
                                  info.email);
+
+  client_->GetPrefs()->CommitPendingWrite();

[xiyuan, 2017/03/16 15:59:02]

nit: Let's add a comment of why this is needed,

e.g.
  // Commit authenticated account info immediately so that it does
  // not get lost if chrome crashes before the next commit interval.

[khmel, 2017/03/16 16:19:43]

Thanks, done

 }
 
 bool SigninManagerBase::IsAuthenticated() const {