Use CHAR_TO_KEY_MAPS in DialpadCharMappings in SmartDialMaps.

This way we don't have to manually keep the maps in sync.

Bug: 30215380,70633239
Test: Existing unit tests
PiperOrigin-RevId: 179871748
Change-Id: Idd4cc1155068bb31c17deae80b98d73363fad770
5 files changed