Use Browser language in login page and loading page when no user info.

[WangLei1993]

Describe the bug

When logout, there is no user info. So the login page is English language for default. Code may in screenshot for fixed.

When loading component is show, sometimes the language may English first and then turn to the user language, sometimes it only show English and then disappeared. And sometimes it only show the user language, it depends on network.

To Reproduce

For one:
Login and choose a different language and then logout to login page.

For two:
Refresh page for many times to see that, for what situation depends on your browser network.

Expected behavior

use browser language translation in these situations.

Screenshots

Environment (please complete the following information):

Master branch code for self test.

[Athou]

I made a change so that the app will try to find a suitable locale for the user before defaulting to English, thank you!