[electron] The 'unload' event listener on the window is never invoked inside electron

[kittaakos]

Description

Try to add some logging, you can see, it works from the browser example, but not from the electron on. The unload listener is not invoked when I refresh the browser window with the electron example. I bet this is related to #6499.

Problematic code:

theia/packages/core/src/browser/frontend-application.ts

Lines 164 to 168 in a8f750a

	window.addEventListener('unload', () => {
	this.stateService.state = 'closing_window';
	this.layoutRestorer.storeLayout(this);
	this.stopContributions();
	});

Reproduction Steps

OS and Theia version:

Diagnostics: