Minor notable behaviour changes in
dom/base/crashtests/1838484.html
dom/html/crashtests/1787671.html
where I changed |window.print();| to |SpecialPowers.wrap(self).printPreview().print()|. I did this because I do not know of a way to close the window that window.print opens (that function doesn't return anything). This should be pretty similar because window.print seems to open a print preview document and then open the print dialog, but doesn't actually trigger the printing (but non-printpreview) code.
For dom/base/crashtests/1838484.html I verified by backing out the patch for bug 1838484 that the modified crashtest still crashes.
I did not do the same verification for dom/html/crashtests/1787671.html because the code has changed significantly since then, and the test seems like it should still test the same issue based on the above.
Differential Revision: https://phabricator.services.mozilla.com/D193344
