code: function markForRemoval(id, mark) {
          if (mark) {
              _idsToRemove[id] = true;
          } else {
              delete _idsToRemove[id];
          }
          exports.trigger("statusChange", id);
      }
docs: Marks an extension for later removal, or unmarks an extension previously marked.
  @param {string} id The id of the extension to mark for removal.
  @param {boolean} mark Whether to mark or unmark it.