Display Default Browser on top in ResolverActivity

This fix is a continuation for fixing 116610086
ResolverComparator identifies that it's dealing with a http/https scheme
The original behaviour was to prefer native apps that can handle that
specific URL over browser apps. This behaviour is preserved with the
exception of the Default Browser, as it will be preferred over all other
apps and will be displayed on top, then will be followed by native apps.

In addition, removed unused imports in ResolverComparator (import
ERRORs that prevented the pre-upload repo hook scripts from passing)

Bug: 116610086
Test: manually tested on device (Pixel 2XL) with multiple users
Test: atest ResolverListControllerTest
Change-Id: Ifd5da932c6f9d9cb4bf0a97985d0f9fb7bc2cb69