Make all input elements display: inline-block by default

[zcorpan]

Fixes #4082

• At least two implementers are interested (and none opposed):
  • Chromium: patch available https://bugs.chromium.org/p/chromium/issues/detail?id=970249#c9
  • Mozilla: already fixed https://bugzilla.mozilla.org/show_bug.cgi?id=1539469
• Tests are written and can be reviewed and commented upon at:
  • HTML: test display and box-sizing UA style for form controls web-platform-tests/wpt#20148
  • Test all input types with scrollTo and onscroll web-platform-tests/wpt#20172 (tentative test for Specify how scrolling works for form controls / widgets #5099)
  • HTML: Add a tentative test for input element's baseline alignment web-platform-tests/wpt#20306 (tentative test for Specify where text baseline is for form controls / widgets #5065)
• Implementation bugs are filed:
  • Chrome:
    • <input> should not honor overflow:scroll/auto
    • UA stylesheet should include table { text-indent: initial } to conform with HTML standard
    • display:inline for <input type=image> when it's not rendering an image (ALT text) should use a true CSS inline box
    • Default display value of form controls should be inline-block
  • Firefox:
    • overflow: hidden !important UA style for input type=file is not interoperable with WebKit/Chromium
    • UA style of option, optgroup, textarea, td are not per spec
  • Safari:
    • <input> should not honor overflow:scroll/auto
    • UA stylesheet should include table { text-indent: initial } to conform with HTML standard

(See WHATWG Working Mode: Changes for more details.)

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/infrastructure.html ( diff )
/rendering.html ( diff )

[zcorpan]

I think this is ready for review; it should address #4082 and some issues raised in comments there.

[zcorpan]

Ping. This change is ready -- it has tests and bugs filed.

Who are appropriate people to review this change and the tests?

[domenic]

@mfreed7 might be another good person for this.

[josepharhar]

I'm working on a fix for this in chrome.
In the diff for this pr, I see that there are special cases for certain types of inputs removed, but it doesn't completely match up with what I changed in chrome.

In this pr it lists reset, button, submit, and color, but in my change for chrome (as per this bug) it changes date, datetime-local, week, time, and month...

[zcorpan]

@josepharhar apologies for the delay.

As far as I can tell, this PR and your change match. All input elements should be inline-block. https://github.com/whatwg/html/pull/4840/files#diff-41cf6794ba4200b839c53531555f0f3998df4cbb01a4d5cb0b94e3ca5e23947dL116936 is a removed line.

Edit: if you mean that the change for the spec and the change for Chromium aren't the same, that would be because Chromium didn't match the spec before. We only need to be concerned about them being the same afterwards. :)

[domenic]

Editorially LGTM. I don't really understand all the changes outside of the UA stylesheet, but I trust @josepharhar's assessment and it seems like there's a really comprehensive list of tests and bugs, so I'm happy for this to be merged whenever @zcorpan thinks it and its tests are ready.

[zcorpan]

I think this is as ready as it will be, so I'm also happy to have it merged.

One referenced test PR is not yet reviewed, but it's tracked in issue #5099, so doesn't need to block this.