Support URI in the Model DOM

[nkoenig]

Signed-off-by: Nate Koenig nate@openrobotics.org

🎉 New feature

Summary

The SdfGenerator code in Ignition Gazebo has a map that associates URIs to models. In order to use the DOM to generate SDF with model <include> elements we need a way to set a model's URI and use the URI in the ToElement function.

This PR support setting a model's URI, and updates the ToElement to use the URI. This won't break ABI because the Model::ToElement has not been released.

Test it

Run the tests.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

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[codecov-commenter]

Codecov Report

Merging #786 (972aa0c) into sdf12 (4a6b5b6) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##            sdf12     #786      +/-   ##
==========================================
+ Coverage   89.53%   89.56%   +0.03%     
==========================================
  Files          76       76              
  Lines       12585    12603      +18     
==========================================
+ Hits        11268    11288      +20     
+ Misses       1317     1315       -2     

Impacted Files	Coverage Δ
src/Model.cc	91.46% <100.00%> (+1.02%)	⬆️

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[osrf-triage]

This pull request has been mentioned on Gazebo Community. There might be relevant details there:

https://community.gazebosim.org/t/new-ignition-releases-2022-04-13-fortress-edifice/1367/1