[Site Design Revamp] Reset header on rotation

[twstokes]

Fixes #18707

Before	After

Note:

Though this fixes the gap, the header tends to "pop" into place which isn't preferred. Ultimately I think it's a better problem to have than the gap.

Testing

1. Start the Site Creation flow in portrait orientation
2. Navigate to the Site Design screen
3. Rotate to landscape
4. Expect there to be no gap at the top
5. Rotate back to portrait
6. Expect there to be no regressions

Regression Notes

1. Potential unintended areas of impact

• Layout of designs when rotating the Site Design screen

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

• Manually tested the steps above

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

• None, as these are UI changes.

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]

	Fails
🚫	Podfile: reference to a commit hash

Generated by 🚫 dangerJS

[wpmobilebot]

You can test the changes in Jetpack from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr18815-d1d749c on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[wpmobilebot]

You can test the changes in WordPress from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr18815-d1d749c on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[mkevins]

Tested on an iPhone 11 (physical device), and it is working well, imo. Also, thanks for noting this:

Though this fixes the gap, the header tends to "pop" into place which isn't preferred. Ultimately I think it's a better problem to have than the gap.

I observed the same, and agree that it's better to not have the gap. Fwiw, even with the gap, the orientation animation has some "jank" anyway, imo, so even more reason to favor this solution. Thanks for addressing this Tanner 👍 .