Edit Image modal:
- Move all advanced options under a single “Show advanced options” toggle that mirrors the behavior and look-and-feel of the wplink modal.
- Switch to using <select> for the Size and Link To.
- Bring back the field for CSS Class for the image, but don’t incorporate the internally managed WordPress classes (size-, wp-image-, etc…).
- On larger screen sizes, float labels to the left. When the width drops below 900px, stack the label above the fields.
- Keep image at top on screen sizes where the two columns are stacked into a single column.
- Don't replace the nodes in the editor DOM so we don't stomp on any custom attributes that the user may have added via the Text editor or some other mechanism.
Props gcorne, see #27366
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git-svn-id: http://core.svn.wordpress.org/trunk@27729 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Gallery preview: add a "No items found" state which is displayed when rendering the gallery wpview and no attachments are found. Props gcorne, fixes #27558
Built from https://develop.svn.wordpress.org/trunk@27899


git-svn-id: http://core.svn.wordpress.org/trunk@27730 1a063a9b-81f0-0310-95a4-ce76da25c4cd
wpLink: fix spinners selectors and add some throttling when searching with AJAX while the user is typing, fixes #27615
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git-svn-id: http://core.svn.wordpress.org/trunk@27731 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Drag and drop files on the editor to upload: add new argument to wp_editor() to enable, fixes #27465
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git-svn-id: http://core.svn.wordpress.org/trunk@27732 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Improve some inline documentation for class properties in `WP_Customize_Section`.

Props leewillis77 for the initial patch.
Fixes #26245.

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git-svn-id: http://core.svn.wordpress.org/trunk@27733 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Second-pass inline documentation improvements for WP_Customize_Widgets.

See #27534.

Built from https://develop.svn.wordpress.org/trunk@27903


git-svn-id: http://core.svn.wordpress.org/trunk@27734 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Coding standards and readability spacing for WP_Customize_Widgets.

Also explicitly re-mark `_capture_filter_pre_update_option()` and `_capture_filter_pre_get_option()` as public.

See #27534.

Built from https://develop.svn.wordpress.org/trunk@27904


git-svn-id: http://core.svn.wordpress.org/trunk@27735 1a063a9b-81f0-0310-95a4-ce76da25c4cd