Chrome on Android returns unavailable languages in its voice list

[HadrienGardeur]

In addition to the problem with the current approach for getVoices() in Chrome for Android detailed in #12, we need to file a separate report about the list of languages itself.

A list of voices should only contain values that the user can use, but that's not the case currently in Chrome for Android. The list contains languages for which the voice pack hasn't been installed yet, which results in the TTS engine using English as a fallback.

Links:

• TBD

Also reported in:

• https://issues.chromium.org/issues/331977824