master
Improve `cache` testing under J2CL and J2KT.
Address places where [CheckedExceptionNotThrown](https://errorprone.info/bugpattern/CheckedExceptionNotThrown) *would* produce warnings if it were to operate on test code.
Run `@LargeTest` tests under Android emulators by default.
Adapt to the once and future TODO style.
Add some `@Nullable` annotations (and one `requireNonNull` call) to `LocalCache` and to `cache` tests.
Rewrite `c.g.c.cache` tests to use Truth assertions.
Address some more counterfactual [CheckedExceptionNotThrown](https://errorprone.info/bugpattern/CheckedExceptionNotThrown) findings.
Reduce visibilities of some overrides to match the inherited methods' visibilities.
Avoid testing identity equality on `Boolean` instances.
Explicitly annotate some null-unmarked classes as `@NullUnmarked`.
Rename the remaining `PackageSanityTests` (plural) classes to "`PackageSanityTest`" (singular).