Unable to clear registry and caches before Drupal update because cache_l10n_update doesnt yet exist

The exact error message is:

Base table or view not found: 1146 Table 'cache_l10n_update' doesn't exist: TRUNCATE {cache_l10n_update} ; Array() in cache_clear_all() (line 167 of includes/cache.inc).

I need to clear my registry (using drush rr) to fix some modules that have moved around and that prevent properly running updates. However at the same time, i cannot use drush rr, because it attempts to clear the cache for a table that does not exist yet (because updates for l10n_update module have not been run yet). A vicious cycle!

I found that adding the following lines around the cache clear calls fixed things. Patch to follow.

    if (db_table_exists('cache_l10n_update')) {
      cache_clear_all('*', 'cache_l10n_update', TRUE);
    }