fix: crash on window.print()

[codebytere]

Description of Change

Fixes #19539.

window.print() doesn't invoke PrintViewManagerBase::PrintNowInternal, so when we moved

  registrar_.Add(this, chrome::NOTIFICATION_PRINT_JOB_EVENT,
                content::NotificationService::AllSources());

into that function from PrintViewManagerBase::CreateNewPrintJob() we inadvertently created a side-effect wherein in PrintViewManagerBase::ReleasePrintJob() it would try to unregister a notification listener which wasn't registered, and would therefore CHECK on found != registered_.end().

This fixes that by guarding the unregistration with a null check on callback_, which would only be non-null when in the call chain of our webContents.print() implementation, since callback_ is a member we patched in ourselves as part of that method.

cc @jkleinsc @PalmerAL @deepak1556

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• PR title follows semantic commit guidelines
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: Fixed a crash in window.print().

[release-clerk]

Release Notes Persisted

Fixed a crash in window.print().

[trop]

I was unable to backport this PR to "6-0-x" cleanly;
you will need to perform this backport manually.

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I was unable to backport this PR to "5-0-x" cleanly;
you will need to perform this backport manually.

[trop]

I have automatically backported this PR to "7-0-x", please check out #19623

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A maintainer has manually backported this PR to "6-0-x", please check out #19677

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A maintainer has manually backported this PR to "5-0-x", please check out #19678

[rgarcia1990]

i have the same problem in electron v9, will it be solved soon?

[codebytere]

@rgarcia1990 this should be fixed in v9. If you are still having issues, please fill out a new issue with a proper repro and other aspects of the template filled.

[rgarcia1990]

@rgarcia1990 this should be fixed in v9. If you are still having issues, please fill out a new issue with a proper repro and other aspects of the template filled.

it seems that the problem is when you try to print a page from version 9 using pdf viewer... it easy to reproduce just load a browserwindow from an url with pdf and try to print.

[rgarcia1990]

@rgarcia1990 this should be fixed in v9. If you are still having issues, please fill out a new issue with a proper repro and other aspects of the template filled.

i created the issue for that problem. It is very important for me if you can help me! Thanks for considering my request!
#24458