code: public void setProfileProxy(int profile, @Nullable BluetoothProfile proxy) {
      isOverridingProxyBehavior = true;
      if (proxy != null) {
        profileProxies.put(profile, proxy);
      }
    }
docs: Sets the active BluetoothProfile {@code proxy} for the given {@code profile}. Will always
  affect behavior of {@link BluetoothAdapter#getProfileProxy} and {@link
  BluetoothAdapter#closeProfileProxy}. Call to {@link BluetoothAdapter#closeProfileProxy} can
  remove the set active proxy.
  
  @param proxy can be 'null' to simulate the situation where {@link
  BluetoothAdapter#getProfileProxy} would return 'false'. This can happen on older Android
  versions for Bluetooth profiles introduced in later Android versions.