refactor(views): clean up creating views in place and extract view_hydrator

Major changes:
- `compiler.compileRoot(el, type)`
  -> `compiler.compileInHost(type) + viewHydrator.hydrateHostViewInPlace(el, view)`
- move all `hydrate`/`dehydrate` methods out of `View` and `ViewContainer` into
  a standalone class `view_hydrator` as private methods and provide new public
  methods dedicated to the individual use cases.

Note: This PR does not change the current functionality, only moves it
into different places.

See design discussion in #1351, in preparation for imperative views.

modules/benchmarks/src/compiler/compiler_benchmark.js

@@ -72,6 +72,7 @@ export function main() {
       new Parser(new Lexer()), shadowDomStrategy, new TemplateLoader(null, urlResolver)
     ),
     null,
+    null,
     shadowDomStrategy
   );
   var compiler = new Compiler(
@@ -81,7 +82,7 @@ export function main() {
     new ComponentUrlMapper(),
     urlResolver,
     renderer,
-    new ProtoViewFactory(dynamicChangeDetection, renderer)
+    new ProtoViewFactory(dynamicChangeDetection)
   );
   var templateNoBindings = createTemplateHtml('templateNoBindings', count);
   var templateWithBindings = createTemplateHtml('templateWithBindings', count);