Modified actions/login.php to redirect logged in users who hit login/ to

the site index.

Removed the throwing of a clientError in favour of a common_redirect to
index to fix Issue 2990: "If logged in, just redirect to home page on
/login"

actions/login.php

@@ -94,8 +94,7 @@ class LoginAction extends Action
         parent::handle($args);
 
         if (common_is_real_login()) {
-            // TRANS: Client error displayed when trying to log in while already logged in.
-            $this->clientError(_('Already logged in.'));
+            common_redirect(common_local_url('index'));
         } else if ($_SERVER['REQUEST_METHOD'] == 'POST') {
             $this->checkLogin();
         } else {