Remove Redundant Null Check in TextEngine
Remove Redundant Null Check in TextEngine

The close caption map cannot be null in text engine, but we were
still checking if it was falsy. Since it can't be null, we can remove
the falsy check.

With the falsy check removed, the expression was able to be reduce
even further.

Change-Id: I839bc2337cfa1415cc6b00b75602e608f75b0e13

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