Failsafe html handling

[ahartikainen]

Description

Clone couple functions from xarray.core and add fail-safe handling html repr.

Checklist

• Follows official PR format
• Includes a sample plot to visually illustrate the changes (only for plot-related functions)
• New features are properly documented (with an example if appropriate)?
• Includes new or updated tests to cover the new feature
• Code style correct (follows pylint and black guidelines)
• Changes are listed in changelog

[codecov]

Codecov Report

Merging #1392 into master will decrease coverage by 0.02%.
The diff coverage is 90.32%.

@@            Coverage Diff             @@
##           master    #1392      +/-   ##
==========================================
- Coverage   91.74%   91.72%   -0.03%     
==========================================
  Files         105      105              
  Lines       10915    10930      +15     
==========================================
+ Hits        10014    10025      +11     
- Misses        901      905       +4     

Impacted Files	Coverage Δ
arviz/plots/separationplot.py	73.68% <ø> (ø)
arviz/utils.py	89.45% <86.66%> (-0.23%)	⬇️
arviz/data/inference_data.py	83.80% <91.66%> (-0.32%)	⬇️
arviz/data/__init__.py	100.00% <100.00%> (ø)
arviz/data/base.py	97.50% <100.00%> (ø)
arviz/data/io_dict.py	92.91% <100.00%> (ø)
arviz/plots/__init__.py	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 89a87ef...2badec4. Read the comment docs.

[ahartikainen]

I think this is ready to merge?

[michaelosthege]

@ahartikainen I suppose you'll do a release of these recent fixes after this got merged?

[ahartikainen]

Yes, I think someone from the dev team will do the release