commit faf7d127540ae5205ac30e4c5e8b8501d7e92619
author Kent Tamura <tkent@chromium.org> Fri Nov 30 03:55:44 2018
committer Commit Bot <commit-bot@chromium.org> Fri Nov 30 03:55:44 2018
tree 0b44d74676627b66ad1ce086c9282faebc32807b
parent c2c37f34472817bd144fcb6cabc88b98ced34ae4

Form-associated custom elements: Support 'disabled' attribute behavior

Form-associated custom elements should support 'disabled' content
attribute and <fieldset disabled> ancestors. It affects form
submission, focusability, :disabled :enabled CSS selectors.

Implementation:
- HTMLElement::IsDisabledFormControl() is hooked to refer to
  ListedElement::IsActuallyDisabled().  This affects :disabled
  selector.
- HTMLElement::MatchesEnabledPseudoClass() is hooked to support
  :enabled selector.
- HTMLElement::AttributeChanged() handles 'disabled' attribute change.
- HTMLElement::SupportsFocus() takes into account
  IsDisabledFormControl()
- ElementInternals::AppendToFormData() aborts if
  IsDisabledFOrmControl().
- HTMLFieldSetElement should handle form-associated custom elements
  as well as HTMLFormControlElements.

- Form-associated checks in ElementInternals is updated so that
  SetFormValue() and 'form' work in constructors.

Note that 'disabledStateChangedCallback' will be implemented by
a following CL.

Bug: 905922
Bug: https://github.com/w3c/webcomponents/issues/187
Change-Id: If4a348b6f3fec5cd6faab6da04ac2de1c228caf7
Reviewed-on: https://chromium-review.googlesource.com/c/1354752
Reviewed-by: Hayato Ito <hayato@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612551}