[web/views/formrenderer] remove `cubicweb:target` attribute on form once the target <iframe> is inserted
For some unknown reason, IE9 does not want to submit the form inside
the <iframe> when the ``cubicweb:target`` attribute exists.
(closes #5377672)
Adrien Di Mascio <Adrien.DiMascio@logilab.fr> [Tue, 16 Jun 2015 18:01:58 +0200] rev 10390
[views] implement a custom json error view
If the client asked for ``(e)jsonexport`` view, answer
him with a json response rather than an error formatted
in a big HTML blob.
add a custom _requested_vid predicate. In cw 3.21, it will
be deprecated in favor of ``match_form_params(vid=('jsonexport', 'ejsonexport'))``