perf(platform-browser): don’t use DomAdapter any more

But use the DOM apis directly.
This also creates a separate `ServerRenderer` implementation
for `platform-server` as it previously reused the `BrowserRenderer`.

modules/@angular/platform-server/testing/server.ts

@@ -9,6 +9,9 @@
 import {platformCoreDynamicTesting} from '@angular/compiler/testing';
 import {NgModule, PlatformRef, Provider, createPlatformFactory} from '@angular/core';
 import {BrowserDynamicTestingModule} from '@angular/platform-browser-dynamic/testing';
+
+import {SERVER_RENDER_PROVIDERS} from '../src/server';
+
 import {INTERNAL_SERVER_PLATFORM_PROVIDERS} from './private_import_platform_server';
 
 
@@ -25,6 +28,6 @@ export const platformServerTesting = createPlatformFactory(
  *
  * @experimental API related to bootstrapping are still under review.
  */
-@NgModule({exports: [BrowserDynamicTestingModule]})
+@NgModule({exports: [BrowserDynamicTestingModule], providers: SERVER_RENDER_PROVIDERS})
 export class ServerTestingModule {
 }