Improve message filters error messages

[ivanpauno]

Replace some errors labeled as "unknown" with a more specific label.

Fixes ros2/rviz#443.
Fixes #118.

[jacobperron]

Thanks for improving this!

[jacobperron]

LGTM

[jacobperron]

I think this just improves the error message, but doesn't actual resolve the repeated warnings on start-up. I.e. it doesn't fix ros2/rviz#513

[ivanpauno]

I think this just improves the error message, but doesn't actual resolve the repeated warnings on start-up. I.e. it doesn't fix ros2/rviz#513

Sounds good, I don't know if that can be completely fixed though.

[jacobperron]

I don't know if that can be completely fixed though.

Yeah, I don't know either. This might be something we could hack around in RViz if it seems to be annoying to users. It might be worth leaving the ticket open and report this improvement on the ticket at least.

[clalancette]

Yeah, I don't know either. This might be something we could hack around in RViz if it seems to be annoying to users. It might be worth leaving the ticket open and report this improvement on the ticket at least.

If I understand what you are talking about here, I think this is just a generic problem with tf2. See #358, which I think is related. This change is obviously an improvement so that the error messages are less generic. But I wouldn't be in favor of suppressing them in RViz, just because all other applications that use tf2 probably have similar issues.

[ivanpauno]

not sure if this can affect downstream packages or not, full CI just in case:

• Linux
• Linux-aarch64
• macOS
• Windows