Convert NotSelectableTargetInfo subtree to factories

Clients of the `NotSelectableTargetInfo` factory methods won't notice
any API change, but those methods will now return instances of
`ImmutableTargetInfo`, built to match the same behavior of the
legacy subtype (note no clients have any remaining `instanceof` checks
in this part of the inheritance graph). The class now just hosts the
static factory methods and some private static helpers, and no longer
inherits from `ChooserTargetInfo` (or any other base). The two
concrete `NotSelectableTargetInfo` subclasses are removed altogether.

This change is a near-pure refactoring; the only other theoretical
difference is that these `NotSelectableTargetInfo` targets will now
get a plausible implementation of `cloneFilledIn()` instead of
returning null, but in practice that method will never actually be
invoked on these particular `TargetInfo` types. We're also *slightly*
more eager in building `IconHolder` instances, but in practice we
would always do that at nearly the same time anyways (and there's no
particular concern about the overhead).

There are also two changes to tests:

 1. The device config permission change seemed to be necessary in
    order to run `TargetInfoTest` in isolation, even though those
    same tests could run as part of `IntentResolverUnitTests` already.
    I'm not sure why the discrepancy, but the fix seems reasonable.

 2. I needed to do a better job of setting up the placeholder targets'
    icon for tests since the new `ImmutableTargetInfo.Builder` API
    doesn't offer a mechanism to override `hasDisplayIcon()` directly.
    With the better support in place, I made some extra assertions.

This is the first (low-hanging-fruit) conversion of this type, and
in future CLs we should proceed through the rest of the hierarchy
before eventually flattening all the APIs into a single class.

Test: `atest TargetInfoTest`
Bug: 202167050
Change-Id: Ibabfee6ef2349de0db0be97f1d2f894d0672cbfd

0 files changed, 0 insertions, 0 deletions