Change record status: 
Project: 
Introduced in branch: 
8.x
Introduced in version: 
7.10
Description: 

This was unfortunately not done in time for the release of Drupal 7.0, so while you can use string context values in t() to designate a specific meaning of a string, this was not possible in JavaScript. Drupal 7 versions > 7.9 and Drupal 8 solves this problem.

PHP in Drupal 7 and 8:

$short_may = t('May');
$long_may = t('May', array(), array('context' => 'Long month name'));

JavaScript in Drupal 7 versions < 7.10:

shortMay = Drupal.t('May');
longMay = .... not possible in JS ....

JavaScript in Drupal 7 versions > 7.9 and Drupal 8:

shortMay = Drupal.t('May');
longMay = Drupal.t('May', {}, {context: "Long month name"});
Updates Done (doc team, etc.)
Online documentation: 
Not done
Theming guide: 
Not done
Module developer documentation: 
Not done
Examples project: 
Not done
Coder Review: 
Not done
Coder Upgrade: 
Not done
Other: 
Other updates done