ARC: Fix Install Source for default installed ARC apps

ArcApps and ArcAppListPrefs were determining the install source for an
ARC app by calling ArcAppListPrefs::IsDefault and ::IsOem with an ARC
package name string. However, these methods take an App ID string, and
so the result was that the preloaded apps were always marked as user
installed. This CL changes the code to use App ID instead, fixing the
issue.

Additionally, this CL reorders the checks for OEM and Default. All OEM
apps are default apps, so we need to check OEM status first.

Bug: 1189949
Change-Id: I147488c707c6515c26d4f6ecc6b58f761d28d912
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3142691


Reviewed-by: Nancy Wang <nancylingwang@chromium.org>
Commit-Queue: Tim Sergeant <tsergeant@chromium.org>
Cr-Commit-Position: refs/heads/main@{#918502}