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/compiler/src/ng_module_compiler.ts

@@ -216,11 +216,15 @@ class _InjectorBuilder implements ClassBuilder {
       result = o.literal(dep.value);
     }
     if (!dep.isSkipSelf) {
-      if (dep.token &&
-          (tokenReference(dep.token) === resolveIdentifier(Identifiers.Injector) ||
-           tokenReference(dep.token) === resolveIdentifier(Identifiers.ComponentFactoryResolver))) {
-        result = o.THIS_EXPR;
+      if (dep.token) {
+        if (tokenReference(dep.token) === resolveIdentifier(Identifiers.Injector)) {
+          result = o.THIS_EXPR;
+        } else if (
+            tokenReference(dep.token) === resolveIdentifier(Identifiers.ComponentFactoryResolver)) {
+          result = o.THIS_EXPR.prop('componentFactoryResolver');
+        }
       }
+
       if (!result) {
         result = this._instances.get(tokenReference(dep.token));
       }