Rewrote the ROI test to use GstVideoRegionOfInterest meta rather
than injecting GstEvents. These meta are added as a pad probe in
the queue src pad.
Also
* Use of navigation messages to control de test
* Use signal watch for processing messages
* Change to H265 rather than H264 since current intel-vaapi-driver
only supports ROI on kabylake.
TODO: add a parameter to change the encoder/decoder to test.
https://bugzilla.gnome.org/show_bug.cgi?id=768248
This implements a pipleint to recognize difference between ROI and non-ROI.
See comments in this code in detail.
https://bugzilla.gnome.org/show_bug.cgi?id=768248
Signed-off-by: Víctor Manuel Jáquez Leal <vjaquez@igalia.com>