In multi display setup, when calibrating secondary display with touch device, touch doesn’t not work. If I disconnect primary display, that makes secondary display as new primary display and touch works just fine.

Steps to reproduce:
1. Identify primary display as display1, and secondary display as display2. Here secondary display is a touch device.
2. Launch weston
3. Execute weston-calibrator on display2 and capture calibration values
4. Exit weston
5. Create a udev rule in /etc/udev/rules.d/weston.rules with calibration values:
Example:
ENV{ID_VENDOR_ID}=="2149",ENV{ID_MODEL_ID}=="2122",ENV{WL_CALIBRATION}="0.994876 -0.013934 12.975220 -0.004180 1.008462 -3.079773"

(I tried udev rule with LIBINPUT_CALIBRATION_MATRIX, touch does not work. Weston still using WL_CALIBRATION, I created udev rule with WL_CALIBRATION)

6. Unplug and replug touch device
7. Restart weston. 
8. Execute weston-simple-touch on display2. Observe touch does not work.
9. Disconnect display1. Observe touch works on display2.

Software Stack:
wayland (HEAD) remotes/origin/HEAD-0-gedf4e7a 
drm (HEAD) heads/master-16-gd686160 
mesa (HEAD) remotes/origin/10.2-0-ge475222 
libva (HEAD) libva-1.3.1-0-g053f70f 
intel-driver (HEAD) 1.3.1-0-ga720bc8 
cairo (HEAD) remotes/origin/1.12-0-g4b65497 
libinput (HEAD) remotes/origin/HEAD-0-g224f1d8 
weston (HEAD) remotes/origin/HEAD-0-gf1d2cc0