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-cli/src/codegen.ts

@@ -11,7 +11,7 @@
  * Intended to be used in a build step.
  */
 import * as compiler from '@angular/compiler';
-import {ComponentMetadata, NgModuleMetadata, ViewEncapsulation} from '@angular/core';
+import {Component, NgModule, ViewEncapsulation} from '@angular/core';
 import {AngularCompilerOptions, NgcCliOptions} from '@angular/tsc-wrapped';
 import * as path from 'path';
 import * as ts from 'typescript';
@@ -62,9 +62,9 @@ export class CodeGenerator {
       const staticType = this.reflectorHost.findDeclaration(absSourcePath, symbol, absSourcePath);
       const annotations = this.staticReflector.annotations(staticType);
       annotations.forEach((annotation) => {
-        if (annotation instanceof NgModuleMetadata) {
+        if (annotation instanceof NgModule) {
           result.ngModules.push(staticType);
-        } else if (annotation instanceof ComponentMetadata) {
+        } else if (annotation instanceof Component) {
           result.components.push(staticType);
         }
       });