feat(NgBaseCss): Add NgBaseCss, which adds css files to all components

lib/core_dom/element_binder.dart

@@ -224,9 +224,10 @@ class ElementBinder {
         Http http = injector.get(Http);
         TemplateCache templateCache = injector.get(TemplateCache);
         DirectiveMap directives = injector.get(DirectiveMap);
+        NgBaseCss baseCss = injector.get(NgBaseCss);
         // This is a bit of a hack since we are returning different type then we are.
         var componentFactory = new _ComponentFactory(node, ref.type, component,
-            injector.get(dom.NodeTreeSanitizer), _expando);
+            injector.get(dom.NodeTreeSanitizer), _expando, baseCss);
         var controller = componentFactory.call(injector, scope, viewCache, http, templateCache,
             directives);
 

lib/core_dom/module_internal.dart

@@ -15,6 +15,8 @@ import 'package:angular/core_dom/dom_util.dart' as util;
 import 'package:angular/change_detection/watch_group.dart' show Watch, PrototypeMap;
 import 'package:angular/core/registry.dart';
 
+import 'package:angular/directive/module.dart' show NgBaseCss;
+
 part 'animation.dart';
 part 'view.dart';
 part 'view_factory.dart';

lib/core_dom/view_factory.dart

@@ -155,14 +155,15 @@ class _ComponentFactory implements Function {
   final NgComponent component;
   final dom.NodeTreeSanitizer treeSanitizer;
   final Expando _expando;
+  final NgBaseCss _baseCss;
 
   dom.ShadowRoot shadowDom;
   Scope shadowScope;
   Injector shadowInjector;
   var controller;
 
   _ComponentFactory(this.element, this.type, this.component, this.treeSanitizer,
-                    this._expando);
+                    this._expando, this._baseCss);
 
   dynamic call(Injector injector, Scope scope,
                ViewCache viewCache, Http http, TemplateCache templateCache,
@@ -178,7 +179,7 @@ class _ComponentFactory implements Function {
     // so change back to using @import once Chrome bug is fixed or a
     // better work around is found.
     List<async.Future<String>> cssFutures = new List();
-    var cssUrls = component.cssUrls;
+    var cssUrls = []..addAll(_baseCss.urls)..addAll(component.cssUrls);
     if (cssUrls.isNotEmpty) {
       cssUrls.forEach((css) => cssFutures.add(http
           .getString(css, cache: templateCache)

lib/directive/module.dart

@@ -20,6 +20,7 @@ import 'package:angular/change_detection/watch_group.dart';
 import 'package:angular/change_detection/change_detection.dart';
 
 part 'ng_a.dart';
+part 'ng_base_css.dart';
 part 'ng_bind.dart';
 part 'ng_bind_html.dart';
 part 'ng_bind_template.dart';
@@ -45,6 +46,7 @@ part 'ng_model_validators.dart';
 class NgDirectiveModule extends Module {
   NgDirectiveModule() {
     value(NgA, null);
+    type(NgBaseCss);  // The root injector should have an empty NgBaseCss
     value(NgBind, null);
     value(NgBindTemplate, null);
     value(NgBindHtml, null);

lib/directive/ng_base_css.dart

@@ -0,0 +1,14 @@
+part of angular.directive;
+
+@NgDirective(
+    selector: '[ng-base-css]',
+    visibility: NgDirective.CHILDREN_VISIBILITY
+)
+class NgBaseCss {
+  List<String> _urls = const [];
+
+  @NgAttr('ng-base-css')
+  set urls(v) => _urls = v is List ? v : [v];
+
+  List<String> get urls => _urls;
+}

test/directive/ng_base_css_spec.dart

@@ -0,0 +1,73 @@
+library ng_base_css_spec;
+
+import '../_specs.dart';
+
+@NgComponent(
+    selector: 'html-and-css',
+    templateUrl: 'simple.html',
+    cssUrl: 'simple.css')
+class _HtmlAndCssComponent {}
+
+main() => describe('NgBaseCss', () {
+  beforeEachModule((Module module) {
+    module
+      ..type(_HtmlAndCssComponent);
+  });
+
+  it('should load css urls from ng-base-css', async((TestBed _, MockHttpBackend backend) {
+    backend
+      ..expectGET('base.css').respond('.base{}')
+      ..expectGET('simple.css').respond('.simple{}')
+      ..expectGET('simple.html').respond('<div>Simple!</div>');
+
+    var element = e('<div ng-base-css="base.css"><html-and-css>ignore</html-and-css></div>');
+    _.compile(element);
+
+    backend.flush();
+    microLeap();
+
+    expect(element.children[0].shadowRoot).toHaveHtml(
+            '<style>.base{}</style><style>.simple{}</style><div>Simple!</div>'
+        );
+  }));
+
+  it('ng-base-css should overwrite parent ng-base-csses', async((TestBed _, MockHttpBackend backend) {
+    backend
+      ..expectGET('base.css').respond('.base{}')
+      ..expectGET('simple.css').respond('.simple{}')
+      ..expectGET('simple.html').respond('<div>Simple!</div>');
+
+    var element = e('<div ng-base-css="hidden.css"><div ng-base-css="base.css"><html-and-css>ignore</html-and-css></div></div>');
+    _.compile(element);
+
+    backend.flush();
+    microLeap();
+
+    expect(element.children[0].children[0].shadowRoot).toHaveHtml(
+        '<style>.base{}</style><style>.simple{}</style><div>Simple!</div>'
+    );
+  }));
+
+  describe('from injector', () {
+    beforeEachModule((Module module) {
+      module.value(NgBaseCss, new NgBaseCss()..urls = ['injected.css']);
+    });
+
+    it('ng-base-css should be available from the injector', async((TestBed _, MockHttpBackend backend) {
+      backend
+        ..expectGET('injected.css').respond('.injected{}')
+        ..expectGET('simple.css').respond('.simple{}')
+        ..expectGET('simple.html').respond('<div>Simple!</div>');
+
+      var element = e('<div><html-and-css>ignore</html-and-css></div></div>');
+      _.compile(element);
+
+      backend.flush();
+      microLeap();
+
+      expect(element.children[0].shadowRoot).toHaveHtml(
+          '<style>.injected{}</style><style>.simple{}</style><div>Simple!</div>'
+      );
+    }));
+  });
+});