String refresh corrupts {locales_source} table

Problem/Motivation

After doing a "Refresh strings" for the Taxonomy text group my database table {locales_source} is corrupted with incorrect records. Example:
record: {location: 'taxonomy:term:167:name', textgroup: 'taxonomy', source: 'some term', context: 'term:167:name'}
while in the taxonomy_term_data table the record with tid='167' is defined as 'other term'.

Source of the error

Debugging this error I found that the array_merge_recursive in function i18n_string_object_type_string_list does not retain the keys as they are seen as being numeric.

function i18n_string_object_type_string_list($type) {
  $strings = array();
  if ($objects = module_invoke_all('i18n_string_objects', $type)) {
    foreach ($objects as $object) {
      if ($object_strings = i18n_object($type, $object)->get_properties()) {
        $strings = array_merge_recursive($strings, $object_strings);
      }
    }
  }
  return $strings;
}

After 2 loops $strings contains:

$strings	Array [1]	
	taxonomy	Array [1]	
		term	Array [3]	
			129	Array [2]	
				name	Array [4]	
					string	(string:19) Vakantiehuis / Gîte	
					title	(string:4) Name	
					format	null	
					name	Array [4]	
						0	(string:8) taxonomy	
						1	(string:4) term	
						2	(string:3) 129	
						3	(string:4) name	
				description	Array [4]	
			130	Array [2]	
				name	Array [4]	
					string	(string:8) Bungalow	
					title	(string:4) Name	
					format	null	
					name	Array [4]	
						0	(string:8) taxonomy	
						1	(string:4) term	
						2	(string:3) 136	
						3	(string:4) name	
				description	Array [4]	

You can see how the 2nd object is indexed with 130, where it should be 136.

Note that this will not only fail for taxonomy term names,but also for term descriptions, and probably other text groups as well, as most will have numeric keys.

Proposed resolution

I don't see any easy solution. drupal_array_merge_deep() won't help here, see the comments of drupal_array_merge_deep_array... If the keys were not really used, we could try to make them real strings by prefixing an 'id:' to all keys. But function i18n_string_refresh_string_list does use them, so that would need to be changed there as well (removing the 'id:').

Another option is to write your own version of the recursive merge...