Placeholders: Update radius temporarily. (#64672)

Co-authored-by: jasmussen <joen@git.wordpress.org>
Co-authored-by: jameskoster <jameskoster@git.wordpress.org>

packages/components/CHANGELOG.md

@@ -22,6 +22,7 @@
 
 ### Enhancements
 
+-   `Placeholder`: Temporarily rewind radius scale ([#64672](https://github.com/WordPress/gutenberg/pull/64672)).
 -   `Composite`: improve Storybook examples and add interactive controls ([#64397](https://github.com/WordPress/gutenberg/pull/64397)).
 -   `Composite`: use internal context to forward the composite store to sub-components ([#64493](https://github.com/WordPress/gutenberg/pull/64493)).
 -   `QueryControls`: Default to new 40px size ([#64457](https://github.com/WordPress/gutenberg/pull/64457)).

packages/components/src/placeholder/style.scss

@@ -19,7 +19,7 @@
 
 
 	// Block UI appearance.
-	border-radius: $radius-medium;
+	border-radius: $radius-small;	// Match the block toolbar material radius.
 	background-color: $white;
 	box-shadow: inset 0 0 0 $border-width $gray-900;
 	outline: 1px solid transparent; // Shown for Windows 10 High Contrast mode.
@@ -144,6 +144,9 @@
 	display: flex;
 	box-shadow: none;
 
+	// In the unselected state, radius should match Global Styles > Image > Radius.
+	border-radius: 0;
+
 	// Blur the background so layered dashed placeholders are still visually separate.
 	// Make the background transparent to not interfere with the background overlay in placeholder-style() pseudo element
 	backdrop-filter: blur(100px);