Widgets panel will not wait to display until the preview loads.
Also fixes problems with `margin-top` in panels where other panels' `active` states change, as well as ensuring sections of deactivated panel collapse before panel is hidden to prevent the pane from becoming empty of controls.
Fixes#33052.
Fixes#33567.
git-svn-id: https://develop.svn.wordpress.org/trunk@35231 602fd350-edb4-49c9-b593-d223f7449a82
* Always fall back to using the default template if no custom template exists.
* Provide a set of default params when constructing new `Section` and `Panel` objects.
Includes QUnit tests.
Props celloexpressions, westonruter, ocean90.
Fixes#30737.
git-svn-id: https://develop.svn.wordpress.org/trunk@32681 602fd350-edb4-49c9-b593-d223f7449a82
Includes tests for the broken `activate()`/`deactivate()` methods, which were fixed in [30871].
props westonruter.
see #30701.
git-svn-id: https://develop.svn.wordpress.org/trunk@30919 602fd350-edb4-49c9-b593-d223f7449a82