fix(compiler): prevent race conditions

Previously, the compiler would detect cycles where there were none just because of other components that were compiled in parallel. Furthermore, the way ProtoView merging was triggered could result into early exits resulting in errors when trying to instantiate ProtoViews.

Fixes #3206
Closes #3211

modules/angular2/test/core/compiler/compiler_spec.ts

@@ -374,7 +374,7 @@ export function main() {
     it('should cache compiled host components', inject([AsyncTestCompleter], (async) => {
          tplResolver.setView(MainComponent, new viewAnn.View({template: '<div></div>'}));
          var mainPv = createProtoView();
-         var compiler = createCompiler([createRenderProtoView()], [rootProtoView, mainPv]);
+         var compiler = createCompiler([createRenderProtoView([])], [rootProtoView, mainPv]);
          compiler.compileInHost(MainComponent)
              .then((protoViewRef) => {
                expect(internalProtoView(protoViewRef).elementBinders[0].nestedProtoView)
@@ -535,7 +535,8 @@ export function main() {
     it('should create host proto views', inject([AsyncTestCompleter], (async) => {
          tplResolver.setView(MainComponent, new viewAnn.View({template: '<div></div>'}));
          var rootProtoView =
-             createProtoView([createComponentElementBinder(directiveResolver, MainComponent)]);
+             createProtoView([createComponentElementBinder(directiveResolver, MainComponent)],
+                             renderApi.ViewType.HOST);
          var mainProtoView = createProtoView();
          var compiler = createCompiler([createRenderProtoView()], [rootProtoView, mainProtoView]);
          compiler.compileInHost(MainComponent)
@@ -694,9 +695,9 @@ class FakeProtoViewFactory extends ProtoViewFactory {
   }
 
   createAppProtoViews(componentBinding: DirectiveBinding, renderProtoView: renderApi.ProtoViewDto,
-                      directives: List<DirectiveBinding>): AppProtoView {
+                      directives: List<DirectiveBinding>): AppProtoView[] {
     this.requests.push([componentBinding, renderProtoView, directives]);
-    return ListWrapper.removeAt(this.results, 0);
+    return collectEmbeddedPvs(ListWrapper.removeAt(this.results, 0));
   }
 }
 
@@ -706,4 +707,17 @@ class MergedRenderProtoViewRef extends renderApi.RenderProtoViewRef {
 
 function originalRenderProtoViewRefs(appProtoView: AppProtoView) {
   return (<MergedRenderProtoViewRef>appProtoView.mergeMapping.renderProtoViewRef).originals;
+}
+
+function collectEmbeddedPvs(pv: AppProtoView, target: AppProtoView[] = null): AppProtoView[] {
+  if (isBlank(target)) {
+    target = [];
+  }
+  target.push(pv);
+  pv.elementBinders.forEach(elementBinder => {
+    if (elementBinder.hasEmbeddedProtoView()) {
+      collectEmbeddedPvs(elementBinder.nestedProtoView, target);
+    }
+  });
+  return target;
 }

modules/angular2/test/core/compiler/projection_integration_spec.ts

@@ -486,4 +486,4 @@ class Tab {
 })
 class Tree {
   depth = 0;
-}
+}

modules/angular2/test/core/compiler/proto_view_factory_spec.ts

@@ -66,10 +66,10 @@ export function main() {
         var varBindings = new Map();
         varBindings.set('a', 'b');
         var renderPv = createRenderProtoView([], null, varBindings);
-        var appPv =
+        var appPvs =
             protoViewFactory.createAppProtoViews(bindDirective(MainComponent), renderPv, []);
-        expect(appPv.variableBindings.get('a')).toEqual('b');
-        expect(appPv).toBeTruthy();
+        expect(appPvs[0].variableBindings.get('a')).toEqual('b');
+        expect(appPvs.length).toBe(1);
       });
     });