refactor(core): remove …Metadata for all decorators and use the decorator directly.

BREAKING CHANGE:
- all `…Metadata` classes have been removed. Use the corresponding decorator
  as constructor or for `instanceof` checks instead.
- Example:
  * Before: `new ComponentMetadata(…)`
  * After: `new Component(…)`
- Note: `new Component(…)` worked before as well.

modules/@angular/compiler/testing/ng_module_resolver_mock.ts

@@ -7,13 +7,13 @@
  */
 
 import {NgModuleResolver} from '@angular/compiler';
-import {Compiler, Injectable, Injector, NgModuleMetadata, Type} from '@angular/core';
+import {Compiler, Injectable, Injector, NgModule, Type} from '@angular/core';
 
 import {Map} from './facade/collection';
 
 @Injectable()
 export class MockNgModuleResolver extends NgModuleResolver {
-  private _ngModules = new Map<Type<any>, NgModuleMetadata>();
+  private _ngModules = new Map<Type<any>, NgModule>();
 
   constructor(private _injector: Injector) { super(); }
 
@@ -22,20 +22,20 @@ export class MockNgModuleResolver extends NgModuleResolver {
   private _clearCacheFor(component: Type<any>) { this._compiler.clearCacheFor(component); }
 
   /**
-   * Overrides the {@link NgModuleMetadata} for a module.
+   * Overrides the {@link NgModule} for a module.
    */
-  setNgModule(type: Type<any>, metadata: NgModuleMetadata): void {
+  setNgModule(type: Type<any>, metadata: NgModule): void {
     this._ngModules.set(type, metadata);
     this._clearCacheFor(type);
   }
 
   /**
-   * Returns the {@link NgModuleMetadata} for a module:
-   * - Set the {@link NgModuleMetadata} to the overridden view when it exists or fallback to the
+   * Returns the {@link NgModule} for a module:
+   * - Set the {@link NgModule} to the overridden view when it exists or fallback to the
    * default
    * `NgModuleResolver`, see `setNgModule`.
    */
-  resolve(type: Type<any>, throwIfNotFound = true): NgModuleMetadata {
+  resolve(type: Type<any>, throwIfNotFound = true): NgModule {
     var metadata = this._ngModules.get(type);
     if (!metadata) {
       metadata = super.resolve(type, throwIfNotFound);