Aux window: move away from globals that need to be contextual

[bpasero]

With floating windows, there is not just one window or document but one per window. Global use of window and document should cause a ESLint warning and utilities should be provided as alternatives.

Adoptions

• $window

//cc @alexdima

[bpasero]

After discussion with Jo: maybe we could patch setTimeout to always run in the active window. This would ensure that throttling does not apply at least for most short living timeouts.

Pending investigation what happens when a window closes that has a timer associated.

[bpasero]

More on setTimeout: we could patch the global window method to schedule the callback on all opened window and then cancel it for the first winner. We would in addition have to schedule it for new windows opening with the diff of the duration.

[bpasero]

The remaining usages of $window are covered in:

• Support iframe based editors to reparent into floating windows #195715
• Aux window: avoid using $window for notebooks #203672

[rebornix]

@bpasero I fixed the $window usage in notebook now.