Use SandboxContext in AbstractDeviceProfileTest

- Added a initializeForTesting method to SandboxContext
- Also made SandboxContext non-abstract, so it can be used in tests to inject mock MainThreadInitializedObject into the SandboxContext, this should avoid mocked MainThreadInitializedObject bled into another test

Test: presubmit
Flag: None
Bug: 303328913
Change-Id: I37157d81b08b80f1e90eacca7dc2ce482cd08aa4
2 files changed