Correct the fallback image in PICTURE element

[mukeshpanchal27]

Summary

This PR accounts following:

• Return image/jpeg as fallback image for Picture element.
• Remove image/jpeg mime from Picture > Source and return only additional mime.
• Use share fixture for tests.
• Add/update unit test that reflect the changes.
• Reinitialize the WP_HTML_Tag_Processor so it check the additional next_tag in while loop.

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Co-authored-by: mukeshpanchal27 <[email protected]>
Co-authored-by: westonruter <[email protected]>
Co-authored-by: joemcgill <[email protected]>
Co-authored-by: adamsilverstein <[email protected]>

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[mukeshpanchal27]

Thanks @westonruter for the feedback. PR ready for review.

[westonruter]

Unless I'm missing something (like the issues I just commented on being addressed elsewhere) this doesn't seem quite there.

[westonruter]

It looks like $this->mock_frontend_body_hooks() needs to be added to the remaining test cases as well. Alternatively, it could be added to set_up instead.

[mukeshpanchal27]

@westonruter @adamsilverstein PR updated and ready for review.

[mukeshpanchal27]

@adamsilverstein @joemcgill Could you please review this when you have a moment? Thanks!

[joemcgill]

This is looking good.

[adamsilverstein]

Fantastic!

[adamsilverstein]

Worked well in my testing, thanks for working on this @mukeshpanchal27 🎉