fix(nav): pop() will unmount views within a modal

[sean-perkins]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
  • Some docs updates need to be made in the ionic-docs repo, in a separate PR. See the contributing guide for details.
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

When popping views with ion-nav used inside of a modal, the views are not unmounted. This results in broken experiences when trying to pop to the previous view or using other APIs dependent on pop, such as popToRoot.

This was caused by inline modals, when the view is constructed ion-nav is disconnected from the view and re-attached. When disconnected, internal state was set to indicate that the Nav component was destroyed. This causes specific unmounting behavior not to fire. This flag was never reset to true when the component connected again.

Issue URL: #25637, #21831

What is the new behavior?

• Views will correctly unmount when they are popped from an ion-nav inside an ion-modal.
• The internal destroyed state of ion-nav is reset when the component is connected to the DOM.
• Refactors internal methods for more explicit awareness to the behavior

Does this introduce a breaking change?

• Yes
• No

Other information

[averyjohnston]

Does this also resolve this issue #21831 or is that something else?

[averyjohnston]

LGTM aside from Liam's comments.

[sean-perkins]

Does this also resolve this issue #21831 or is that something else?

@amandaejohnston this should resolve that issue as well. I'll update the PR description to account for it 👍