fix: element injector vs module injector (#15044)

fixes #12869
fixes #12889
fixes #13885
fixes #13870

Before this change there was a single injector tree.
Now we have 2 injector trees, one for the modules and one for the components.
This fixes lazy loading modules.

See the design docs for details:
https://docs.google.com/document/d/1OEUIwc-s69l1o97K0wBd_-Lth5BBxir1KuCRWklTlI4

BREAKING CHANGES

`ComponentFactory.create()` takes an extra optional `NgModuleRef` parameter.
No change should be required in user code as the correct module will be used
when none is provided

DEPRECATIONS

The following methods were used internally and are no more required:
- `RouterOutlet.locationFactoryResolver`
- `RouterOutlet.locationInjector`

packages/core/src/linker/component_factory.ts

@@ -11,6 +11,7 @@ import {Injector} from '../di/injector';
 import {Type} from '../type';
 
 import {ElementRef} from './element_ref';
+import {NgModuleRef} from './ng_module_factory';
 import {ViewRef} from './view_ref';
 
 /**
@@ -72,6 +73,7 @@ export abstract class ComponentFactory<C> {
   /**
    * Creates a new component.
    */
-  abstract create(injector: Injector, projectableNodes?: any[][], rootSelectorOrNode?: string|any):
-      ComponentRef<C>;
+  abstract create(
+      injector: Injector, projectableNodes?: any[][], rootSelectorOrNode?: string|any,
+      ngModule?: NgModuleRef<any>): ComponentRef<C>;
 }

packages/core/src/linker/component_factory_resolver.ts

@@ -6,12 +6,12 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {Injector} from '../di/injector';
 import {Type} from '../type';
 import {stringify} from '../util';
 
-import {ComponentFactory} from './component_factory';
-
-
+import {ComponentFactory, ComponentRef} from './component_factory';
+import {NgModuleRef} from './ng_module_factory';
 
 export function noComponentFactoryError(component: Function) {
   const error = Error(
@@ -44,7 +44,9 @@ export abstract class ComponentFactoryResolver {
 export class CodegenComponentFactoryResolver implements ComponentFactoryResolver {
   private _factories = new Map<any, ComponentFactory<any>>();
 
-  constructor(factories: ComponentFactory<any>[], private _parent: ComponentFactoryResolver) {
+  constructor(
+      factories: ComponentFactory<any>[], private _parent: ComponentFactoryResolver,
+      private _ngModule: NgModuleRef<any>) {
     for (let i = 0; i < factories.length; i++) {
       const factory = factories[i];
       this._factories.set(factory.componentType, factory);
@@ -52,10 +54,22 @@ export class CodegenComponentFactoryResolver implements ComponentFactoryResolver
   }
 
   resolveComponentFactory<T>(component: {new (...args: any[]): T}): ComponentFactory<T> {
-    let result = this._factories.get(component);
-    if (!result) {
-      result = this._parent.resolveComponentFactory(component);
-    }
-    return result;
+    let factory = this._factories.get(component) || this._parent.resolveComponentFactory(component);
+
+    return factory ? new ComponentFactoryBoundToModule(factory, this._ngModule) : null;
+  }
+}
+
+export class ComponentFactoryBoundToModule<C> extends ComponentFactory<C> {
+  constructor(private factory: ComponentFactory<C>, private ngModule: NgModuleRef<any>) { super(); }
+
+  get selector() { return this.factory.selector; }
+  get componentType() { return this.factory.componentType; }
+
+  create(
+      injector: Injector, projectableNodes?: any[][], rootSelectorOrNode?: string|any,
+      ngModule?: NgModuleRef<any>): ComponentRef<C> {
+    return this.factory.create(
+        injector, projectableNodes, rootSelectorOrNode, ngModule || this.ngModule);
   }
 }

packages/core/src/linker/ng_module_factory.ts

@@ -11,8 +11,7 @@ import {Type} from '../type';
 import {stringify} from '../util';
 
 import {ComponentFactory} from './component_factory';
-import {CodegenComponentFactoryResolver, ComponentFactoryResolver} from './component_factory_resolver';
-
+import {CodegenComponentFactoryResolver, ComponentFactoryBoundToModule, ComponentFactoryResolver} from './component_factory_resolver';
 
 
 /**
@@ -62,10 +61,7 @@ export class NgModuleFactory<T> {
   get moduleType(): Type<T> { return this._moduleType; }
 
   create(parentInjector: Injector): NgModuleRef<T> {
-    if (!parentInjector) {
-      parentInjector = Injector.NULL;
-    }
-    const instance = new this._injectorClass(parentInjector);
+    const instance = new this._injectorClass(parentInjector || Injector.NULL);
     instance.create();
     return instance;
   }
@@ -73,18 +69,21 @@ export class NgModuleFactory<T> {
 
 const _UNDEFINED = new Object();
 
-export abstract class NgModuleInjector<T> extends CodegenComponentFactoryResolver implements
-    Injector,
-    NgModuleRef<T> {
+export abstract class NgModuleInjector<T> implements Injector, NgModuleRef<T> {
+  bootstrapFactories: ComponentFactory<any>[];
+  instance: T;
+
   private _destroyListeners: (() => void)[] = [];
   private _destroyed: boolean = false;
-
-  public instance: T;
+  private _cmpFactoryResolver: CodegenComponentFactoryResolver;
 
   constructor(
       public parent: Injector, factories: ComponentFactory<any>[],
-      public bootstrapFactories: ComponentFactory<any>[]) {
-    super(factories, parent.get(ComponentFactoryResolver, ComponentFactoryResolver.NULL));
+      bootstrapFactories: ComponentFactory<any>[]) {
+    this.bootstrapFactories =
+        bootstrapFactories.map(f => new ComponentFactoryBoundToModule(f, this));
+    this._cmpFactoryResolver = new CodegenComponentFactoryResolver(
+        factories, parent.get(ComponentFactoryResolver, ComponentFactoryResolver.NULL), this);
   }
 
   create() { this.instance = this.createInternal(); }
@@ -92,9 +91,14 @@ export abstract class NgModuleInjector<T> extends CodegenComponentFactoryResolve
   abstract createInternal(): T;
 
   get(token: any, notFoundValue: any = THROW_IF_NOT_FOUND): any {
-    if (token === Injector || token === ComponentFactoryResolver) {
+    if (token === Injector || token === NgModuleRef) {
       return this;
     }
+
+    if (token === ComponentFactoryResolver) {
+      return this._cmpFactoryResolver;
+    }
+
     const result = this.getInternal(token, _UNDEFINED);
     return result === _UNDEFINED ? this.parent.get(token, notFoundValue) : result;
   }
@@ -103,7 +107,7 @@ export abstract class NgModuleInjector<T> extends CodegenComponentFactoryResolve
 
   get injector(): Injector { return this; }
 
-  get componentFactoryResolver(): ComponentFactoryResolver { return this; }
+  get componentFactoryResolver(): ComponentFactoryResolver { return this._cmpFactoryResolver; }
 
   destroy(): void {
     if (this._destroyed) {