Update backbone method dependencies.

Former-commit-id: 1b030f0a7b2f4065ec1dfc9ef911de77ebd7d842

build.js

@@ -220,6 +220,7 @@
     'max',
     'min',
     'mixin',
+    'once',
     'pick',
     'reduce',
     'reduceRight',

test/backbone.html

@@ -29,10 +29,15 @@
 			);
 		</script>
 		<script src="test-ui.js"></script>
+		<script src="../lodash.js"></script>
 		<script>
+			var lodash = _.noConflict();
 			document.write('<script src="../' + ui.buildPath + '"><\/script>');
 		</script>
 		<script>
+			_.mixin({
+				'debounce': lodash.debounce
+			});
 			if (!_.chain) {
 				_.mixin({
 					'chain': function(value) {

test/test-build.js

@@ -229,6 +229,7 @@
     'max',
     'min',
     'mixin',
+    'once',
     'pick',
     'reduce',
     'reduceRight',