The intensity pattern is just the classically expected two bands corresponding to the two slits. By detecting the electron at the slits, we know through which it went. The wavefunction collapses to an eigenstate. Therefore either A1 = 1 and A2 = 0 or A1 = 0 and A2 = 1. There will be no interference term an the intensity is just the sum of the two one slit intensities.