Custom header logo broken for auto-created users

Summary

If a user is automatically created after login in via LDAP the first time, he is automatically redirected to /profile on each request to fill out the missing data. This, however, also applies to uploaded files, in particular an uploaded custom logo. The logo appears as a "broken image" in the browser.

Screenshot_at_2017-07-19_16_49_54

Steps to reproduce

Upload custom header logo (called "logo.png" in this example). Log-in via LDAP for the first time. The logo is broken. Any request to /uploads/system/appearance/header_logo/1/logo.png is answered with a 301, redirecting to /profile.