Fix CTS breakage in Context and Override configurations

The base Activity resources need to be created differently so that
other configuration contexts can be rebased properly.
Bug:33166230
Test: cts-tradefed run cts --module CtsAndroidAppTestCases --test android.app.cts.ApplyOverrideConfigurationTests

Change-Id: I86def4e2414dc366dd1d5cbc9104c5d0c06a4d61