feat(StyleUrlResolver): rewrite url in styles

modules/angular2/test/core/compiler/style_url_resolver_spec.js

@@ -0,0 +1,41 @@
+import {describe, it, expect, beforeEach, ddescribe, iit, xit, el} from 'angular2/test_lib';
+import {StyleUrlResolver} from 'angular2/src/core/compiler/style_url_resolver';
+
+import {UrlResolver} from 'angular2/src/core/compiler/url_resolver';
+
+export function main() {
+  describe('StyleUrlResolver', () => {
+    it('should resolve urls', () => {
+      var styleUrlResolver = new StyleUrlResolver(new FakeUrlResolver());
+      var css = `
+      @import '1.css';
+      @import "2.css";
+      @import url('3.css');
+      @import url("4.css");
+
+      .foo {
+        background-image: url("double.jpg");
+        background-image: url('simple.jpg');
+      }`;
+      var expectedCss = `
+      @import 'base/1.css';
+      @import 'base/2.css';
+      @import url('base/3.css');
+      @import url('base/4.css');
+
+      .foo {
+        background-image: url('base/double.jpg');
+        background-image: url('base/simple.jpg');
+      }`;
+
+      var resolvedCss = styleUrlResolver.resolveUrls(css, 'base');
+      expect(resolvedCss).toEqual(expectedCss);
+    });
+  });
+}
+
+class FakeUrlResolver extends UrlResolver {
+  resolve(baseUrl: string, url: string): string {
+    return baseUrl + '/' + url;
+  }
+}