refactor(render): create and store render ProtoViewRef in every app ProtoView

Needed to change Renderer.mergeChildComponentProtoViews to not create
new ProtoViews to be able to deal with cyclic references.

This commit is part of using the new render layer in Angular.

modules/angular2/src/render/api.js

@@ -141,20 +141,20 @@ export class Renderer {
   compile(template:Template):Promise<ProtoView> { return null; }
 
   /**
-   * Creates a new ProtoView with preset nested components,
+   * Sets the preset nested components,
    * which will be instantiated when this protoView is instantiated.
+   * Note: We can't create new ProtoViewRefs here as we need to support cycles / recursive components.
    * @param {List<ProtoViewRef>} protoViewRefs
    *    ProtoView for every element with a component in this protoView or in a view container's protoView
-   * @return {List<ProtoViewRef>}
-   *    new ProtoViewRef for the given protoView and all of its view container's protoViews
    */
-  mergeChildComponentProtoViews(protoViewRef:ProtoViewRef, protoViewRefs:List<ProtoViewRef>):List<ProtoViewRef> { return null; }
+  mergeChildComponentProtoViews(protoViewRef:ProtoViewRef, componentProtoViewRefs:List<ProtoViewRef>) { return null; }
 
   /**
    * Creats a ProtoView that will create a root view for the given element,
    * i.e. it will not clone the element but only attach other proto views to it.
+   * Contains a single nested component with the given componentId.
    */
-  createRootProtoView(selectorOrElement):ProtoViewRef { return null; }
+  createRootProtoView(selectorOrElement, componentId):Promise<ProtoView> { return null; }
 
   /**
    * Creates a view and all of its nested child components.