Dismiss suggestions on space keystroke

[guarani]

Addresses WordPress/gutenberg#24425 (for iOS)

Note: This PR replaces #16601 which was reverted after it was found that the PR overlooked updating analytics events.

This PR allows users to easily dismiss the suggestion UI by typing a space character after triggering the UI. This means it will now be easier to add a @ character to a post without triggering the mentions suggestions UI, or add a + character without triggering the cross-post suggestions UI.

I added this change to suggestions in the block editor, but didn't apply it to other parts of the app (e.g. comments, notification replies, etc) because that felt too far out-of-scope here. It would also make the testing steps much longer.

To test:

- [ ] Verify user can dismiss @-mention suggestions on space keystroke
  - Type a space after a `@` character, expect the mentions suggestions list to be dismissed
  - Expect that the `wpios_suggestion_session_finished` Tracks event fires with the `did_select_suggestion` custom property set to `false`
- [ ] Verify user can dismiss cross-post suggestions on space keystroke  
  - Type a space after a `+` character, expect the cross-positing suggestions list to be dismissed
  - Expect that the `wpios_suggestion_session_finished` Tracks event fires with the `did_select_suggestion` custom property set to `false`
- [ ] Verify user can still @-mention another user
  - Expect the recipient of the @-mention to be notified
  - Expect that the `wpios_suggestion_session_finished` Tracks event fires with the `did_select_suggestion` custom property set to `true`
- [ ] Verify user can still cross-post to another site
  - Expect the recipient site to receive the cross-post
  - Expect the `wpios_suggestion_session_finished` Tracks event fires with the `did_select_suggestion` custom property set to `false`

Regression Notes

1. Potential unintended areas of impact

This change could conceivably break suggestions (both mentions and cross-posting).

2. What I did to test those areas of impact (or what existing automated tests I relied on)

The above manual tests.

3. What automated tests I added (or what prevented me from doing so)

This change affects the UI so a UI test would be best, but we only add UI tests to core flows.

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[peril-wordpress-mobile]

You can trigger optional UI/connected tests for these changes by visiting CircleCI here.

[peril-wordpress-mobile]

You can test the changes on this Pull Request by downloading it from AppCenter here with build number: 51676. IPA is available here. If you need access to this, you can ask a maintainer to add you.

[guarani]

Testing 7b74c84 on iPhone 11:

• Verify user can dismiss @-mention suggestions on space keystroke
  • Type a space after a @ character, expect the mentions suggestions list to be dismissed
  • Expect that the wpios_suggestion_session_finished Tracks event fires with the did_select_suggestion custom property set to false
• Verify user can dismiss cross-post suggestions on space keystroke
  • Type a space after a + character, expect the cross-positing suggestions list to be dismissed
  • Expect that the wpios_suggestion_session_finished Tracks event fires with the did_select_suggestion custom property set to false
• Verify user can still @-mention another user
  • Expect the recipient of the @-mention to be notified
  • Expect that the wpios_suggestion_session_finished Tracks event fires with the did_select_suggestion custom property set to true
• Verify user can still cross-post to another site
  • Expect the recipient site to receive the cross-post
  • Expect the wpios_suggestion_session_finished Tracks event fires with the did_select_suggestion custom property set to true

[guarani]

Would you mind reviewing this @enejb when you get a chance? The only difference between this and #16601 (which you reviewed) is that this PR handles analytics properly.

[SiobhyB]

@guarani, I just wanted to share that the Android side was approved and I (perhaps too hastily!) merged it today. Let me know if that seems okay to you or if you think it'd be best to revert the merge in order to make sure these are both aligned.

[guarani]

@guarani, I just wanted to share that the Android side was approved and I (perhaps too hastily!) merged it today. Let me know if that seems okay to you or if you think it'd be best to revert the merge in order to make sure these are both aligned.

Sorry @SiobhyB, I missed this ping. I'd say it's OK 👍 It shouldn't be a problem.

[enejb]

Nice work! This tested for me as advertised.