Add logic for excluding group workaround dependencies

[cottsay]

See ros-infrastructure/catkin_pkg#369

• Linux
• Linux-aarch64
• Windows

[nuclearsandwich]

As I understand it, this isn't conditional is that colcon-ros already supports group dependencies (within the workspace, which is the only context in which it supports any dependencies) and so it should already not need this workaround.

If that's correct then we're all good. If I'm mistaken and there's a different reason it's not conditional I'd prefer another crack at reviewing after being corrected on the rationale.

[cottsay]

colcon-ros already supports group dependencies (within the workspace, which is the only context in which it supports any dependencies) and so it should already not need this workaround

Correct.

[cottsay]

We're going to need to block this change for now. Turns out that we actually have some messed up group unrolling in ROS 2 and this change exposes those bugs.

Who knew that manually curating a list of group members in downstream packages would be error prone?

I'll probably end up enabling this eventually as a feature flag once that change lands.

[cottsay]

We're going to need to block this change for now.

After thinking about it, we actually don't. This doesn't change behavior in any manifests which aren't annotated with the workaround skipping logic, so a long as we fix the group unrolling at the same time, we'll never regress anything.