strtr will issue a notice in user->format_date on at least php 5.5.0

I'm not entirely sure when this started, but it must be in between php 5.3.2 and 5.5.0. Anyway, the thing is php will now output a notice when strtr is called with multidimensional $replace_pairs array, even if the array entries are not used.

And this is precisely what occurs in includes/sessions.php, where format_date will call strtr with one array in the $date_cache[$format]['lang'] entry (the AGO key).

From my experience, the result is not altered, strtr works just as before, but throws a notice on recent versions.

<?php

$str = 'hi all, I said hello';

$replace_pairs = array(

	'all' => 'everybody',

	'unused' => array('somtehing', 'something else'),

	'hello' => 'hey',

);

// php 5.5.0 Notice: Array to string conversion in test.php on line 9

echo strtr($str, $replace_pairs); // hi everybody, I said hey

Replacing strtr with @strtr seems a working solution.