report_webkit translation_call does not pass proper name

We are having issues translating webkit reports correctly.

If a certain translateable term happens to be the same src value as on another report (both webkit and non-webkit reports) the resulting translation on a webkit report uses the first translation found (which is highly likely to be from the other report)

This is not logical, think about the "State" variable issues we had before, how State should be translated is highly dependant on the report and context.

Cause: not passing a proper name to ir_translation._get_source(...)
http://bazaar.launchpad.net/~openerp/openobject-addons/7.0/view/head:/report_webkit/webkit_report.py#L194

Suggestion: Instead of passing the template name (or path which can be hard to determine) I would suggest you use the service name this is guaranteed to be unique after all. While this is indeed quite a big change it should be possible to make it backwards compatible by first checking and if no result was found only then try the new method of searching on service name.