No ticker: grunt_compare_size options. Close gh-1210.

(cherry picked from commit 1f530e28)

Gruntfile.js

@@ -7,6 +7,7 @@ module.exports = function( grunt ) {
 			"dist/jquery.min.map",
 			"dist/jquery.min.js"
 		],
+    gzip = require("gzip-js"),
 		readOptionalJSON = function( filepath ) {
 			var data = {};
 			try {
@@ -19,7 +20,15 @@ module.exports = function( grunt ) {
 		pkg: grunt.file.readJSON("package.json"),
 		dst: readOptionalJSON("dist/.destination.json"),
 		compare_size: {
-			files: distpaths
+			files: [ "dist/jquery.js", "dist/jquery.min.js" ],
+			options: {
+				compress: {
+					gz: function( contents ) {
+						return gzip.zip( contents, {} ).length;
+					}
+				},
+				cache: "dist/.sizecache.json"
+			}
 		},
 		selector: {
 			destFile: "src/selector-sizzle.js",

package.json

@@ -30,6 +30,7 @@
 		"grunt-contrib-jshint": "0.1.1rc6",
 		"grunt-contrib-uglify": "0.1.2",
 		"grunt": "0.4.1",
+		"gzip-js": "0.3.1",
 		"testswarm": "0.2.2"
 	},
 	"keywords": []