Media & Text: Allow drag n drop media replacement

[Mamaduka]

Description

Adds dropzone to the media part of the block when an image/video is already set. Fixes #26320.

How has this been tested?

Manually on local dev environment.

Steps:

1. Add the "Media & Text" block to the post.
2. Add media.
3. Drag and drop media replacement.
4. See if the dropzone indicator appears.
5. See if media is replaced.

Types of changes

New feature

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• I've tested my changes with keyboard and screen readers.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.

[github-actions]

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[draganescu]

Howdy @Mamaduka and welcome! Thank you for contributing. I tested this PR and it does work, but it would be great if the block would show something is happening upon drag. Here is a video comparing to how the image block handles drag and drop:

dropmediatext.mp4

[Mamaduka]

Thanks, @draganescu for testing the PR.

100% with you about the upload indicator.

I'm reusing the PlaceholderContainer component. I'm not sure if those changes should be part of this PR or be a separate one.

[Mamaduka]

Hi, @draganescu

After thinking more about this, it makes sense to include Spinner change as a part of this PR. See b4033b3.

[Mamaduka]

Hi, @draganescu

Is it possible to get another review on this PR? 🙇

[jasmussen]

Sorry about the delay on this one. In fact the branch was so old I had to rebase it in order to compile it 🙈

You can always feel free to request a review from me in the future if you get stalled.

Here's before:

Here's after:

Very nice. It could use a code sanity check, and I'd recommend giving it a good rebase first. But giving it a green check for the experience. Excellent work.

[Mamaduka]

Thanks for the review, @jasmussen.

Rebased and will merge once all checks are green 🤞

[draganescu]

Thanks for chiming in @jasmussen and sorry for not following up @Mamaduka! Nevertheless 🎉 great work!