Thanks to everyone who’s contributed to the fixes.
libpcl-dev is now available on xenial armhf https://github.com/ros/rosdistro/issues/11583
And the srdfdom regression has been resolved. https://github.com/ros-planning/srdfdom/issues/23
The only outstanding issue is the collada_dom issue in robot_model: https://github.com/ros/robot_model/issues/149