Disable background page scrolling when modals are open.

props celloexpressions.
fixes #29074.

git-svn-id: https://develop.svn.wordpress.org/trunk@29346 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/css/common.css

@@ -218,6 +218,10 @@ body.iframe {
 	padding-top: 1px;
 }
 
+body.modal-open {
+	overflow: hidden;
+}
+
 iframe,
 img {
 	border: 0;

src/wp-admin/css/themes.css

@@ -409,10 +409,6 @@
 	z-index: 10;
 }
 
-body.theme-overlay-open {
-	overflow: hidden;
-}
-
 .theme-overlay .theme-header {
 	position: absolute;
 	top: 0;

src/wp-admin/js/theme.js

@@ -701,7 +701,7 @@ themes.view.Details = wp.Backbone.View.extend({
 	// Performs the actions to effectively close
 	// the theme details overlay
 	closeOverlay: function() {
-		$( 'body' ).removeClass( 'theme-overlay-open' );
+		$( 'body' ).removeClass( 'modal-open' );
 		this.remove();
 		this.unbind();
 		this.trigger( 'theme:collapse' );
@@ -1000,7 +1000,7 @@ themes.view.Themes = wp.Backbone.View.extend({
 
 		// Sets this.view to 'detail'
 		this.setView( 'detail' );
-		$( 'body' ).addClass( 'theme-overlay-open' );
+		$( 'body' ).addClass( 'modal-open' );
 
 		// Set up the theme details view
 		this.overlay = new themes.view.Details({