Set default val for color a11y repos

This caused a systemui crash when QS edit button was tapped.
Now we set the default value when reading color a11y settings the way the old tiles did (with value 0).

Flag: aconfig com.android.systemui.qs_new_tiles DEVELOPMENT
Fixes: 322994294
Test: atest SystemUiRoboTests
Test: atest ColorCorrectionRepositoryImplTest
ColorInversionRepositoryImplTest

Change-Id: Idd987ff223d69cd63723fda0b78f779cde20c2db