shadows/framework/src/main/java/org/robolectric/shadows/ShadowTelephonyManager.java
public void setSignalStrength(SignalStrength signalStrength) {
    this.signalStrength = signalStrength;
    for (PhoneStateListener listener :
        getListenersForFlags(PhoneStateListener.LISTEN_SIGNAL_STRENGTHS)) {
      listener.onSignalStrengthsChanged(signalStrength);
    }
  }
public void setSignalStrength(SignalStrength signalStrength) {
    this.signalStrength = signalStrength;
    for (PhoneStateListener listener :
        getListenersForFlags(PhoneStateListener.LISTEN_SIGNAL_STRENGTHS)) {
      listener.onSignalStrengthsChanged(signalStrength);
    }
  }
Sets the value to be returned by {@link #getSignalStrength()}