Tests: Straighten out sinon dependencies

* Cherry-pick took the wrong lines for a couple of things.
* Update and commit dependencies after `grunt bower`

Gruntfile.js

@@ -59,7 +59,8 @@ module.exports = function( grunt ) {
 				},
 				files: {
 					"qunit": "qunit/qunit",
-					"require.js": "requirejs/require.js"
+					"require.js": "requirejs/require.js",
+					"sinon/fake_timers.js": "sinon/lib/sinon/util/fake_timers.js"
 				}
 			}
 		},

test/index.html

@@ -16,8 +16,7 @@
 
 	<script src="libs/qunit/qunit.js"></script>
 	<script src="libs/require.js"></script>
-
-	<script src="../bower_modules/sinon/fake_timers.js"></script>
+	<script src="libs/sinon/fake_timers.js"></script>
 	<!-- See testinit for the list of tests -->
 	<script src="data/testinit.js"></script>