[app-layout] Align overlay breakpoint with other components

[rolandoisidoro]

Using App Layout with a Menu Bar on its Navbar section, I noticed that the App Layout drawer presents an overlay effect starting at 800px (included), while the Menu Bar (which extends Context Menu) gets the same treatment at 750px (not included).

This creates an awkward behavior for devices with resolutions as follow, when used in portrait orientation mode:

• 1024x768;
• 1280x800;
• 1366x768.

[web-padawan]

Thanks for the issue. This is indeed something that we have to improve in future versions.

Please see also https://github.com/vaadin/vaadin-core/issues/241 where I collected breakpoints we have.