Expose APIs for clearing the ECMs internal state tracking addition and removal (backport #3002)

[mergify]

🎉 New feature

Summary

This is necessary for use with the SetState API. This API is commonly used to create a local version of the servers ECM that is periodically synchronized. However, without exposing this function into our public API additions and removals of entities or components are not reflected in the local ECM.

Currently, we use friend relationships for the GuiRunner class to allow it to run these functions, but this is not feasible for external code that wants to use SetState.

gz-sim/include/gz/sim/EntityComponentManager.hh

Lines 833 to 838 in 5ce62a8

	// Make runners friends so that they can manage entity creation and
	// removal. This should be safe since runners are internal
	// to Gazebo.
	friend class GuiRunner;
	friend class SimulationRunner;

gz-sim/src/gui/GuiRunner.cc

Lines 316 to 318 in 5ce62a8

	this->dataPtr->ecm.ClearRemovedComponents();
	this->dataPtr->ecm.ClearNewlyCreatedEntities();
	this->dataPtr->ecm.ProcessRemoveEntityRequests();

This is needed for gazebosim/ros_gz#790 to be able to get the updated state of the world, for example, when requested for the list of entities in the world after an entity has been removed.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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---

This is an automatic backport of pull request #3002 done by Mergify.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 69.09%. Comparing base (e7ef48e) to head (25c4aef).
⚠️ Report is 1 commits behind head on gz-sim9.

Additional details and impacted files

@@             Coverage Diff             @@
##           gz-sim9    #3126      +/-   ##
===========================================
+ Coverage    69.07%   69.09%   +0.01%     
===========================================
  Files          347      347              
  Lines        34038    34037       -1     
===========================================
+ Hits         23512    23518       +6     
+ Misses       10526    10519       -7     

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[azeey]

@Mergifyio rebase

[mergify]

rebase

✅ Branch has been successfully rebased