Keep text track visibility and createMediaState cosistent
Keep text track visibility and createMediaState cosistent

Only create Text media state when the subtitle is visible.

As a follow up for commit Icaa1477d35633fc3afabcf7baf38acde0cd775ef.
Closes #1412.

Change-Id: I4810c4790fd904f4e45dfd1481dab19c7c887920

shaka-project/shaka-player,TheModMaker/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,TheModMaker/shaka-player,tvoli/shaka-player,TheModMaker/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,tvoli/shaka-player,TheModMaker/shaka-player,shaka-project/shaka-player