Index: wp-admin/css/widgets.css
===================================================================
--- wp-admin/css/widgets.css	(revision 29208)
+++ wp-admin/css/widgets.css	(working copy)
@@ -35,6 +35,23 @@
 	user-select: none;
 }
 
+/* Widget Dashicon Styles */
+.wp-widget-icon {
+	margin-left: .8em;
+	margin-top: .8em;
+	float: left;
+} 
+
+.customize-control .wp-widget-icon {
+	margin-left: .8em;
+	margin-top: .7em;
+	float: left;
+}
+
+	.wp-widget-icon+h4, .customize-control .wp-widget-icon+h4 {
+		padding-left: 7px;
+	}
+		
 .widgets-holder-wrap .widget-inside {
 	border-top: none;
 	padding: 1px 15px 15px 15px;
Index: wp-includes/widgets.php
===================================================================
--- wp-includes/widgets.php	(revision 29208)
+++ wp-includes/widgets.php	(working copy)
@@ -83,10 +83,11 @@
 	 *	 - width: required if more than 250px
 	 *	 - height: currently not used but may be needed in the future
 	 */
-	public function __construct( $id_base, $name, $widget_options = array(), $control_options = array() ) {
+	public function __construct( $id_base, $name, $icon_url, $widget_options = array(), $control_options = array() ) {
 		$this->id_base = empty($id_base) ? preg_replace( '/(wp_)?widget_/', '', strtolower(get_class($this)) ) : strtolower($id_base);
 		$this->name = $name;
-		$this->option_name = 'widget_' . $this->id_base;
+		$this->icon_url = is_array($icon_url) || empty($icon_url) ? '' : $icon_url; // create the icon url parameter
+		$this->option_name = 'widget_' . $this->id_base;		
 		$this->widget_options = wp_parse_args( $widget_options, array('classname' => $this->option_name) );
 		$this->control_options = wp_parse_args( $control_options, array('id_base' => $this->id_base) );
 	}
@@ -94,8 +95,8 @@
 	/**
 	 * PHP4 constructor
 	 */
-	public function WP_Widget( $id_base, $name, $widget_options = array(), $control_options = array() ) {
-		WP_Widget::__construct( $id_base, $name, $widget_options, $control_options );
+	public function WP_Widget( $id_base, $name, $icon_url, $widget_options = array(), $control_options = array() ) {
+		WP_Widget::__construct( $id_base, $name, $icon_url, $widget_options, $control_options );
 	}
 
 	/**