Fix failing login when Authorize form is non-English

[akirk]

Fixes WordPress/matrix#6. Thanks @javiercasares for flagging and helping debug!

[akirk]

@ashfame I wonder why the response was completely empty, though. Do you recall what $response->send() is supposed to do here? Should we just echo an error message?

[ashfame]

@akirk I checked, $response->send() simply uses the parameters set on $response to prepare the JSON output. In this case, neither there was any data nor any errors set on the object, hence was just a white screen. Now, I have set a 403 error if authorization on user consent fails, in addition to your fix.

Gonna get this deployed now.

[ashfame]

Great find! Thanks for fixing!