FIX: Ensure callback delegates are created for ActionMaps added after an asset has already assigned to PlayerInput component (case ISXB-711)

[AlexTyrer]

Description

PlayerInput component - ensure any added action map delegates are updated on ActivateInput() (case ISXB-711)

If action maps are added to an asset after the asset has been assigned to the PlayerInput component then the delegates need to be updated.

Before this change no OnXXX callbacks for the newly added ActionMaps were created leading to input loss.

Adding this sync in the ActivateInput() seems like the best compromise.

Testing status & QA

Local testing using supplied user project.
Automated tests

Overall Product Risks

Small change to update the action map callback delegates in ActivateInput.

• Complexity: 1
• Halo Effect: 0

Comments to reviewers

None in particular.

Checklist

Before review:

• Changelog entry added.
  • Explains the change in Changed, Fixed, Added sections.
  • For API change contains an example snippet and/or migration example.
  • JIRA ticket linked, example (case %%). If it is a private issue, just add the case ID without a link.
  • Jira port for the next release set as "Resolved".
• Tests added/changed, if applicable.
  • Functional tests Area_CanDoX, Area_CanDoX_EvenIfYIsTheCase, Area_WhenIDoX_AndYHappens_ThisIsTheResult.
  • Performance tests.
  • Integration tests.
• Docs for new/changed API's.
  • Xmldoc cross references are set correctly.
  • Added explanation how the API works.
  • Usage code examples added.
  • The manual is updated, if needed.

During merge:

• Commit message for squash-merge is prefixed with one of the list:
  • NEW: ___.
  • FIX: ___.
  • DOCS: ___.
  • CHANGE: ___.
  • RELEASE: 1.1.0-preview.3.

After merge:

• Create forward/backward port if needed. If you are blocked from creating a forward port now please add a task to ISX-1444.

[ekcoh]

Fix looks good to me, would it be possible to add a test case that covers this scenario to avoid future regression?