Enable R8 for settings

Keep constructor which is only used directly from test.

Update Proguard configuration to include information on checked
exceptions for Mockity to mock thorwn exception.

Bug: 74756073
Test: atest
com.android.settings.deviceinfo.storage.StorageAsyncLoaderTest#testRemovedPackageDoesNotCrash
Utf8ByteLengthFilterTest
Change-Id: Iae87e6647b28ee69d38bd8891df46239779c459c
3 files changed