Output link/meta tags depending on web app manifest display value

[jefferyto]

This changes when the (apple-)mobile-web-app-capable meta tags (and apple-touch-startup-image link tag) are printed to match the display mode set in the web app manifest.

This also removes the apple-touch-fullscreen meta tag, as this tag has the same effect as the apple-mobile-web-app-capable meta tag but is not included in any Safari documentation.

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[jefferyto]

@googlebot I signed it!

[westonruter]

This also removes the apple-touch-fullscreen meta tag, as this tag has the same effect as the apple-mobile-web-app-capable meta tag but is not included in any Safari documentation.

Yes, I can confirm that at https://stackoverflow.com/a/10040966/93579

[codecov-commenter]

Codecov Report

Merging #581 (906c820) into develop (714d850) will increase coverage by 0.22%.
The diff coverage is 88.88%.

@@              Coverage Diff              @@
##             develop     #581      +/-   ##
=============================================
+ Coverage      17.28%   17.51%   +0.22%     
- Complexity       296      300       +4     
=============================================
  Files             55       55              
  Lines           1770     1776       +6     
=============================================
+ Hits             306      311       +5     
- Misses          1464     1465       +1     

Flag	Coverage Δ
php	17.51% <88.88%> (+0.22%)	⬆️
unit	17.51% <88.88%> (+0.22%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
wp-includes/class-wp-web-app-manifest.php	54.86% <88.88%> (+1.59%)	⬆️

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[westonruter]

Thanks!

[pooja-muchandikar]

QA Passed ✅

On registering new plugin with following code was able to print meta tags based on the display value set in the code.

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