Revert "fixes #4574"

This reverts commit 81a45cfcf1.

lib/base.php

@@ -826,17 +826,12 @@ class OC {
 		) {
 			return false;
 		}
-		// don't redo authentication if user is already logged in
-		// otherwise session would be invalidated in OC_User::login with 
-		// session_regenerate_id at every page load
-		if (!OC_User::isLoggedIn()) {
 		OC_App::loadApps(array('authentication'));
 		if (OC_User::login($_SERVER["PHP_AUTH_USER"], $_SERVER["PHP_AUTH_PW"])) {
 			//OC_Log::write('core',"Logged in with HTTP Authentication", OC_Log::DEBUG);
 			OC_User::unsetMagicInCookie();
 			$_SERVER['HTTP_REQUESTTOKEN'] = OC_Util::callRegister();
 		}
-		}
 		return true;
 	}