Pre-work to decouple ChooserGridAdapter

This first CL introduces a new delegate interface and injects all
the dependencies required to make `ChooserGridAdapter` a static inner
class. Then the next follow-up CL can extract it to the new `grid/`
directory to remove a large chunk of code from the `ChooserActivity`
monolith, including a significant portion of our "UI layer."

Test: atest IntentResolverUnitTests
Bug: 202167050
Change-Id: I86bac2d3dec615c92043bfb01399af62747cc42b
2 files changed