Index: src/wp-admin/js/dashboard.js
===================================================================
--- src/wp-admin/js/dashboard.js	(revision 26372)
+++ src/wp-admin/js/dashboard.js	(working copy)
@@ -2,17 +2,21 @@
 var ajaxWidgets, ajaxPopulateWidgets, quickPressLoad;
 
 jQuery(document).ready( function($) {
-	/* Dashboard Welcome Panel */
-	var welcomePanel = $('#welcome-panel'),
+	var $window = $(window),
+		welcomePanel = $('#welcome-panel'),
 		welcomePanelHide = $('#wp_welcome_panel-hide'),
-		updateWelcomePanel = function( visible ) {
-			$.post( ajaxurl, {
-				action: 'update-welcome-panel',
-				visible: visible,
-				welcomepanelnonce: $('#welcomepanelnonce').val()
-			});
-		};
+		updateWelcomePanel,
+		metaboxHolder = $('.metabox-holder'),
+		updateColumnCount;
 
+	updateWelcomePanel = function( visible ) {
+		$.post( ajaxurl, {
+			action: 'update-welcome-panel',
+			visible: visible,
+			welcomepanelnonce: $('#welcomepanelnonce').val()
+		});
+	};
+
 	if ( welcomePanel.hasClass('hidden') && welcomePanelHide.prop('checked') ) {
 		welcomePanel.removeClass('hidden');
 	}
@@ -128,19 +132,9 @@
 		e.preventDefault();
 	});
 
-	// Dashboard columns
-	jQuery(document).ready(function () {
-		// Update main column count on load
-		updateColumnCount();
-	});
-
-	jQuery(window).resize( _.debounce( function(){
-		updateColumnCount();
-	}, 30) );
-
-	function updateColumnCount() {
+	updateColumnCount = function(window, holder) {
 		var cols = 1,
-			windowWidth = parseInt(jQuery(window).width(), 10);
+			windowWidth = parseInt(window.width(), 10);
 
 		if (799 < windowWidth && 1299 > windowWidth) {
 			cols = 2;
@@ -153,7 +147,14 @@
 		if (1800 < windowWidth) {
 			cols = 4;
 		}
-		jQuery('.metabox-holder').attr('class', jQuery('.metabox-holder').attr('class').replace(/columns-\d+/, 'columns-' + cols));
-	}
+		holder.attr('class', holder.attr('class').replace(/columns-\d+/, 'columns-' + cols));
+	};
 
+	// Update main column count on load
+	updateColumnCount($window, metaboxHolder);
+
+	$window.resize( _.debounce( function(){
+		updateColumnCount($window, metaboxHolder);
+	}, 30) );
+
 } );