Replace field injection with constructor  injection.

This fixes an issue we are having with an upgrade to Kotlin 2.0.21.

See the presubmits on https://r.android.com/3290825.

Generally, field injection should be avoided in favor of constructor
injection, so hopefully this is a change for the better.

Bug: 369137871
Flag: EXEMPT Minor refactor
Test: m ThemePickerApplicationLib
Change-Id: I718113e103da303ddfb102b73c95f9a9b25da132
3 files changed