Street address line 2 does not have a field name (fails accessibility requirements)

[ziranshang]

Street address line 2 does not have a field name: https://github.com/google/libaddressinput/blob/master/android/src/main/java/com/android/i18n/addressinput/AddressWidget.java#L388

This means it does not have a hint or label, so it fails accessibility testing.

[jmealo]

This would be very useful! 👍