Customizer: Make "Search widgets" input sticky.

props celloexpressions.
fixes #30751.
Built from https://develop.svn.wordpress.org/trunk@31227


git-svn-id: http://core.svn.wordpress.org/trunk@31208 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/css/customize-widgets-rtl.css

@@ -338,7 +338,7 @@ body.adding-widget .add-new-widget:before {
 #available-widgets {
 	position: absolute;
 	overflow: auto;
-	top: 0;
+	top: 46px;
 	bottom: 0;
 	right: -301px;
 	width: 300px;
@@ -351,7 +351,13 @@ body.adding-widget .add-new-widget:before {
 }
 
 #available-widgets-filter {
+	position: fixed;
+	top: 0;
+	z-index: 1;
+	width: 300px;
+	height: 46px;
 	padding: 8px 13px 7px 17px;
+	background: #eee;
 	border-bottom: 1px solid #e4e4e4;
 	-webkit-box-sizing: border-box;
 	-moz-box-sizing: border-box;

wp-admin/css/customize-widgets.css

@@ -338,7 +338,7 @@ body.adding-widget .add-new-widget:before {
 #available-widgets {
 	position: absolute;
 	overflow: auto;
-	top: 0;
+	top: 46px;
 	bottom: 0;
 	left: -301px;
 	width: 300px;
@@ -351,7 +351,13 @@ body.adding-widget .add-new-widget:before {
 }
 
 #available-widgets-filter {
+	position: fixed;
+	top: 0;
+	z-index: 1;
+	width: 300px;
+	height: 46px;
 	padding: 8px 17px 7px 13px;
+	background: #eee;
 	border-bottom: 1px solid #e4e4e4;
 	-webkit-box-sizing: border-box;
 	-moz-box-sizing: border-box;

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-alpha-31226';
+$wp_version = '4.2-alpha-31227';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.