[mythtv] 2019-render and Fire TV

[Peter Bennett]

I tried disabling the "OpenGL extra stage" switch. It was previously 
causing blank screen intermittently on Fire tv 4k. I am now unable to 
recreate the blank screen with master branch or with render branch. That 
does not say it has definitely been fixed. I will see if I can do more 
extensive testing.

Fire Stick (non-4K) using mediacodec with opengl-hw -
mpeg2 interlaced - plays ok but a bit jerky
h264 720p - hangs. I see the first frame, then nothing more and does not 
respond to remote.

Fire Stick 4k
mpeg2 interlaced was never able to play using mediacodec, and that 
problem still exists with mediacodec decode.
using mediacodec & opengl-hw:
mpeg2 - very jerky & messages "MediaCodecInterop: Timed out waiting for 
frame update" about 1 per second.
h264 - 720p - 1280x720 picture shows in top Left hand part of screen (it 
seems picture has not been expanded to fill 1920x1080). Messages 
"MediaCodecInterop: Timed out waiting for frame update" about 10 per second.
h264 1080i - I see tearing of the picture, plus the fact that there is 
no deinterlace.

Peter