1119562 - If the printing progress dialog is open, show errors through it instead of a new modal dialog

Status: NEW

(Toolkit :: Printing, defect)

Description

[Mike Conley (:mconley) (:⚙️)]

In bug 1117936, I found out that the e10s printing work for non-e10s windows causes the print progress dialog close to become asynchronous. The problem with this is that errors that occur during the computing of the document for printing result in a modal alert dialog box showing up, anchored to the most recent window (which is, almost assuredly, the print progress dialog).

This means that an alert blocks a dialog. nsPrintEngine then attempts to close the print progress dialog, but it can't, because the print progress dialog is being blocked the modal we just opened.

What I suggest instead is that if we hit an error while the print progress dialog is open, we should display the message in the print progress dialog instead. The print progress dialog "becomes" the error message, that the user then can exit.