Yarp: OVR headset device does not work with the latest version of yarp

[GiulioRomualdi]

I updated yarp to the latest version of devel and the device of the ovr headset is not running.
We are using the yarp in devel and Oculus SDK version is 1.40.0. (is there a particular version of the sdk that should be used?)
This the log file for the error:
log_icub-virtualizer_yarpdev_7848.txt

This is what I can see when I connect the ports.

cc @aerydna @S-Dafarra @kouroshD @DanielePucci @Nicogene

[GiulioRomualdi]

Looking at the code I discovered that the error

<ERROR> FrameTransformClient::getTransform() frames  mobile_base_body_link  and  head_link  are not connected 

is triggered only when the relative mode is enabled in the ovrheadset device.

In a previous version of yarp the relative mode was disabled.
https://github.com/robotology/yarp/commit/b2800f222352cd0cc410f6826269d432460b691a#diff-512556b5de879621a97ebd62f0575b8aL290

Now the relative flag is not set so the behavior of the code may be unpredictable.
What do you think about passing the relative parameter from configuration? I can propose a PR

[GiulioRomualdi]

This commit https://github.com/GiulioRomualdi/yarp/commit/aef216e33857c077d16cdd264510e192f439462c should fix the bug

[drdanz]

@GiulioRomualdi Thanks for investigating this. Can you please open a pull request proposing these changes on master?

@aerydna Can you please have a look at the suggested changes?

[aerydna]

ok for me!

[drdanz]

Fixed by #2106