language direction API : locale_get_direction ($locale)

This issue is splitted from the RTL API decisions on the the general core language direction (RTL) support discussion.

To summerize the above thread:

Currently, anyone who needs to know the language direction must hardcode it.

It was decided that locale.module should information about the language direction.

After dries review, it was decided to add the language direction information to the database - I've opened an issue for saving the information in the locales_meta table, suggesting that such information will be stored in a new properties field.

The previous suggested function was :

function locale_get_direction ($locale) {
  $result = db_query("SELECT direction from {locales_meta} where locale='%lid' ", $locale);
  if ($row = db_fetch_object($result)) {
    return $row->direction;
  }
  else return FALSE;
}

Now, if we are using a properties field, we should fetch the 'direction' property from the field, so the code should be a little different - I don't know how to do it, but it should be something like that:

function locale_get_direction ($locale) {
  $result = db_query("SELECT data from {locales_meta} where locale='%lid' ", $locale);
  if ($row = db_fetch_object($result)) {
    $direction = @get_direction_information ($row->data); /* How to get the property? */
    return $direction;
  }
  else return FALSE;
}

Please commit!