Fixes hot restart correctly reset the browser history

[chunhtai]

web engine hot restart does not tear down the browser history. When the app restarted, it confused itself with the existing browser history, thus causes error in flutter/flutter#73793.

fixes flutter/flutter#73793

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[chunhtai]

Hi @mdebbar is there a way to test this? I couldn't find an example to trigger hard reload during the test.

[mdebbar]

I don't think there's a way to test hot restart yet. Maybe @yjbanov has some thoughts?

[mdebbar]

Thanks for fixing this!

[mdebbar]

I don't think there's a way to test hot restart yet. Maybe @yjbanov has some thoughts?

[mdebbar]

The pattern that we use in the web engine is to call registerHotRestartListener and pass a callback. The callback will be invoked when hot restart is requested.

So somewhere near the code that initializes the history, you could do:

registerHotRestartListener(() {
  window.resetHistory();
});

Example:

engine/lib/web_ui/lib/src/engine/platform_dispatcher.dart

Lines 768 to 770 in 42019c8

	registerHotRestartListener(() {
	_removeBrightnessMediaQueryListener();
	});