chore(browsers): fix failing tests in Firefox

Closes #3386

modules/angular2/test/render/dom/view/proto_view_merger_integration_spec.ts

@@ -267,8 +267,8 @@ export function main() {
                  tb.merge([rootProtoViewDto, componentProtoViewDto])
                      .then(mergeMappings => {
                        var domPv = resolveInternalDomProtoView(mergeMappings.mergedProtoViewRef);
-                       expect(DOM.getInnerHTML(templateRoot(domPv)))
-                           .toEqual('<root class="ng-binding" a="b"></root>');
+                       expect(stringifyElement(templateRoot(domPv)))
+                           .toEqual('<template><root a="b" class="ng-binding"></root></template>');
                        async.done();
                      });
                });