(a) The TTS API doesn't mandate that unavailable voices should
be set and null, so deal with it correctly.
(b) The android manifest contained a reference to the old
TTS class.
bug:5525023
Change-Id: I1c16dbc75893288e5fa221c73a7284fca7ab25c5
Re-added if there are voices to install.
DO NOT MERGE : Was already submitted to master.
bug:5511343
Change-Id: Iac95f37c3dda3b213f6ba34c32b7dc725673d64d