UIA/search field: exclude Microsoft Edge's address omnibar from becoming a search field

[josephsl]

Hi,

Based on #9110 but more generalized:

Is your feature request related to a problem? Please describe.

As part of #6241, search suggestions and search field detection became possible. Back then, Edge's address omnibar (for classic Edge) was also recognized as a search field due to the work being based on an add-on.

Over time, it has become apparent that Edge's address omnibar support needed more tweaking. One prominent problem is the fact that controller for event is fired by Edge's address omnibar when Edge becomes maximized (see #9110 for details), along with address completion not being read (see #8838). In case of the first problem, it was traced to the fact that the address bar was treated as a search field, thereby living with controller for event for an element not currently focused at the moment, and for the second, auto-select wasn't used due to older assumptions about UIA auto-select (pull request in progress in #9660).

Describe the solution you'd like

Given the above issues, it is proposed that Classic Edge's address omnibar be excluded from becoming a search field. Not only this resolves #9110, it also prepares that element to participate in #9660 PR. Also, now that we have an app module for Edge (both the host and the content process), any tweaks for that element should be part of that app module, with base UIA search field used to cover search fields across Windows and apps.

Describe alternatives you've considered

Leave it as is. Solution then becomes adding an overlay class in Edge app module that prevents controller for (more specifically, suggestions closed) event being fired when the address omnibar loses focus.

Additional context

Although #9660 can benefit Edge's address omnibar, a pull request for this issue is independent of that work. Also, the next generation of Edge is based on Chromium, so this does not apply there.

Thanks.