Field stylers now determine whether they've been applied to the target field
on their own, which solves the problem of the system getting out of sync.
* src/ui/styler/ErrorFieldStyler.js (isApplied): Added
* src/ui/styler/FieldStyler.js (isApplied): Added
* src/ui/styler/NaFieldStyler.js (isApplied): Added
* test/ui/styler/NaFieldStylerTest.js: Test for #isApplied
This is necessarily primarily for a specific case: option elements in IE,
which cannot be styled. >:O
This implementation is not complete: we want to re-attach the field at the
same position it was at before it was detached. This might not be
trivial---imagine if its sibling was also detached.
* src/ui/styler/NaFieldStyler.js (isSubField): Receive field instead of
element (to check parent)
(applyStyle, revokeStyle): Detach and re-attach field from/to DOM
respectively
* test/ui/styler/NaFieldStylerTest.js: Associated tests
Mike Gerwitz