Misaligned buttons when editing a post slug

[SergeyBiryukov]

See the screenshot.

[mattheu]

I looked into this bug and noticed a couple of issues.

• The new input field styles are too large in this context. This causes alignment issues with the buttons, and also the the height of the #edit-slug-box is larger when the input is visible, causing a jump in the page when showing/hiding the input.
• The button-small styles are a little inconsistent across the admin. Within the colorpicker on the theme customizer, they have a smaller font, and larger height.

I have added a patch that

1. Reduces the size of the edit permalink input, and reduces the font size to match the label text. This is a 1 off style for this input.
2. Move the styles from .wp-picker-input-wrap .button.button-small and apply to all .button-small

This makes everything line up a bit nicer. See screenshot.

There are a couple of other places in the admin that the button-small class is used, but I tested them and there are no issues created by making this change. They are as follows:

• In the taxonomy search field on the menu edit page. But this is hidden.
• On the press this field when adding an image. But this still looks fine.

[iammattthomas]

In 26420:

Unify the style of button-small everywhere we use it, and make sure the edit slug input lines up with its button and label. Fixes #26261, props mattheu.