Ensure *# are included in TTS spans generated with PhoneNumberUtils.

PhoneNumber utils has a method, createTtsSpan, which creates a span
for talkback to speak a phone number.  Due to a bug in Talkback it used
to strip out * and # characters.

Removing this limitation as the bug in talkback has been fixed.

Test: Manual, added unit tests
Bug: 63613215
Change-Id: I983a98a18830e32760602723e695f11e3eab9ffe