[Settings] Replace Robolectric#setupActivity()

Avoid from accessing Robolectric#setupActivity().

Bug: 140707056
Test: make RunSettingsRoboTests ROBOTEST_FILTER=EuiccPreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataServiceSetupPreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=ApnPreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=DataUsagePreferenceControllerTest
Test: make RunSettingsRoboTests ROBOTEST_FILTER=SubscriptionsPreferenceControllerTest
Change-Id: I8552b181d2dc1c9a5d8aeb0b7e79bbec7252f67e
5 files changed