Fix SafetyProtectionUtils

This util was expecting getString() and getDrawable() to return null
when resource is not found but it's actually throwing an exception.
Changed the logic in this class to expect an exception when the
resource it not available

Bug: 269874157
Test: SafetyProtectionTest
Change-Id: I0f3490b59dc2427c2889e25fea529c85d3e1f150