Convert block_admin_add() in block.admin.inc to the new form interface

Initial patch.

You want to use the magic in the routing definition:

views_ui.add:
  pattern: '/admin/structure/views/add'
  defaults:
    _entity_form: 'view.add'
  requirements:
    _permission: 'administer views'

With that you should be able to do everything without an extra controller.

Helper http://drupal.org/node/1913618

We are working today with this issue during Code Sprint UA

#2: convert_block_admin_add_to_controller-1983874-2.patch queued for re-testing.

+++ b/core/modules/block/lib/Drupal/block/BlockAddController.phpundefined
@@ -0,0 +1,30 @@
+class BlockAddController {
...
+  public function blockAddRender($plugin_id, $theme) {

Is there maybe a better name for this method/class? Please move this file into the Controller directory instead of the rootnamespace.

+++ b/core/modules/block/lib/Drupal/block/BlockAddController.phpundefined
@@ -0,0 +1,30 @@
+   $entity = entity_create('block', array(
+     'plugin' => $plugin_id,
+     'theme' => $theme,
+   ));

In a perfect world this controller would get the entity manager injected and use ->getStorageController('block')->create(...) instead of entity_create.

Here are the fixes. Please review.

#9: block-convert-block-admin-add-to-controller-1983874-9.patch queued for re-testing.

Let's fix it but also not use a global method anymore.

It seems ok to me!

Forgot to set rtbc

Committed 54e9f29 and pushed to 8.x. Thanks!