Clean up MozL10n API use in Cost Control #1057795

This is relating bug 1057795
As we refactor mozL10n to use L20n API, we intend to introduce mozL10n.localize method, and preserving the obsolete name that will be different from how the method is named in mozL10n while overlap with a different method from mozL10n is going to be more confusing.

For that reason we want to get rid of all "localize" methods now, especially ones that set L10n realted DOM attributes.

For more details see https://developer.mozilla.org/en-US/docs/Mozilla/Projects/L20n/Javascript_API#ctx.localize%28ids.3A_Array%3CString%3E.2C_callback.3A_Function%29