constructor({urlData,
   viewCacheCapacity,
   shadowDomStrategy,
   templates}) {
   this._templates = MapWrapper.create();
   if (isPresent(templates)) {
     ListWrapper.forEach(templates, (template) => {
       MapWrapper.set(this._templates, template.componentId, template);
     });
   }
   this._compileCache = MapWrapper.create();
   var parser = new Parser(new Lexer());
   var urlResolver = new UrlResolver();
   if (isBlank(shadowDomStrategy)) {
     shadowDomStrategy = new EmulatedUnscopedShadowDomStrategy(new StyleUrlResolver(urlResolver), null);
   }
   var compiler = new Compiler(new DefaultStepFactory(parser, shadowDomStrategy), new FakeTemplateLoader(urlResolver, urlData));
   if (isBlank(viewCacheCapacity)) {
     viewCacheCapacity = 1;
   }
   if (isBlank(urlData)) {
     urlData = MapWrapper.create();
   }
   this.eventPlugin = new FakeEventManagerPlugin();
   var eventManager = new EventManager([this.eventPlugin], new FakeVmTurnZone());
   var viewFactory = new ViewFactory(viewCacheCapacity, eventManager, shadowDomStrategy);
   this.renderer = new DirectDomRenderer(compiler, viewFactory, shadowDomStrategy);
   this.rootEl = el('<div></div>');
   this.rootProtoViewRef = this.renderer.createRootProtoView(this.rootEl);
 }

 _compileRecurse(template) {
   var result = MapWrapper.get(this._compileCache, template.componentId);
   if (isPresent(result)) {
     return result;
   }
   result = this.renderer.compile(template).then((pv) => {
     var childComponentPromises = ListWrapper.map(this._findNestedComponentIds(template, pv), (componentId) => {
       var childTemplate = MapWrapper.get(this._templates, componentId);
       if (isBlank(childTemplate)) {
         throw new BaseException(`Could not find template for ${componentId}!`);
       }
       return this._compileRecurse(childTemplate);
     });
     return PromiseWrapper.all(childComponentPromises).then((protoViewRefsWithChildren) => {
       var protoViewRefs = ListWrapper.map(protoViewRefsWithChildren, (arr) => arr[0]);
       return this._flattenList([this.renderer.mergeChildComponentProtoViews(pv.render, protoViewRefs), protoViewRefsWithChildren]);
     });
   });
   MapWrapper.set(this._compileCache, template.componentId, result);
   return result;
 }

 return PromiseWrapper.all(childComponentPromises).then((protoViewRefsWithChildren) => {
   var protoViewRefs = ListWrapper.map(protoViewRefsWithChildren, (arr) => arr[0]);
   return this._flattenList([this.renderer.mergeChildComponentProtoViews(pv.render, protoViewRefs), protoViewRefsWithChildren]);
 });