Use custom .isInvalid() for GL shader (fixes #31)
Use custom .isInvalid() for GL shader (fixes #31)

madrazo/lime-1,fbricker/lime,fbricker/lime,openfl/lime,player-03/lime,player-03/lime,player-03/lime,MinoGames/lime,madrazo/lime-1,fbricker/lime,openfl/lime,madrazo/lime-1,MinoGames/lime,madrazo/lime-1,fbricker/lime,player-03/lime,madrazo/lime-1,MinoGames/lime,fbricker/lime,MinoGames/lime,MinoGames/lime,player-03/lime,madrazo/lime-1,openfl/lime,player-03/lime,MinoGames/lime,fbricker/lime,openfl/lime,openfl/lime,MinoGames/lime,madrazo/lime-1,fbricker/lime,openfl/lime,openfl/lime,player-03/lime