Support dynamic route parameters to enhance comment admin paths with entity type and field name from comment bundle

Nice clean up. It is almost RTBC just minor things.

1. +++ b/core/modules/comment/lib/Drupal/comment/Routing/CommentBundleEnhancer.php
   @@ -0,0 +1,51 @@
   +  public function __construct(EntityManager $entity_manager) {
   

   @param missing.

2. +++ b/core/modules/comment/tests/Drupal/comment/Tests/Routing/CommentBundleEnhancerTest.php
   @@ -0,0 +1,60 @@
   +    $request = new Request();
   +    $defaults = array('bundle' => 'node__comment');
   +    $new_defaults = $route_enhancer->enhance($defaults, $request);
   ...
   +    $request = new Request();
   +    $defaults = array('bundle' => 'node__field_foobar');
   +    $new_defaults = $route_enhancer->enhance($defaults, $request);
   

   This seems like a good use of dataProvider.

Thank you @larowlan for the fixes :). Now we have more test ;). Clean code. I think it is api clean up.

1. +++ b/core/modules/comment/tests/Drupal/comment/Tests/Routing/CommentBundleEnhancerTest.php
   @@ -0,0 +1,101 @@
   +  /**
   +   * Data provider for testEnhancer().
   +   *
   +   * @see testEnhancer()
   +   *
   +   * @return array
   +   *   An array of arrays containing strings:
   +   *     - The bundle name.
   +   *     - The commented entity type.
   +   *     - The field name.
   +   */
   +  public function providerTestEnhancer() {
   +    return array(
   +      array(
   +        'node__comment',
   +        'comment',
   +        'node',
   +      ),
   +      array(
   +        'node__comment_forum__schnitzel',
   +        'comment_forum__schnitzel',
   +        'node',
   +      ),
   +      array(
   +        'node__field_foobar',
   +        FALSE,
   +        FALSE
   +      ),
   +    );
   +  }
   

   Wow this is called beauty :D.

2. +++ b/core/modules/comment/tests/Drupal/comment/Tests/Routing/CommentBundleEnhancerTest.php
   @@ -0,0 +1,101 @@
   +        // Test two sets of __.CommentManager
   

   CommentManager is a typo :P. Please can we fix it on commit :$.

1. +++ b/core/modules/comment/lib/Drupal/comment/Routing/CommentBundleEnhancer.php
   @@ -0,0 +1,54 @@
   +    $bundles = $this->entityManager->getBundleInfo('comment');
   

   Can we move it to the if() so that the bundles are not loaded on every routing request.

2. +++ b/core/modules/comment/lib/Drupal/comment/Routing/CommentBundleEnhancer.php
   @@ -0,0 +1,54 @@
   +    if (isset($defaults['bundle']) && isset($bundles[$defaults['bundle']])) {
   

   Just looking at this line I am wondering whether this is maybe too generic. Isn't there quite a high chance that someone will put also 'bundle' into the route and it will magically adds these values even not needed?

3. +++ b/core/modules/comment/tests/Drupal/comment/Tests/Routing/CommentBundleEnhancerTest.php
   @@ -0,0 +1,101 @@
   +/**
   + * Tests the comment bundle enhancer route enhancer.
   + *
   + * @see \Drupal\comment\Routing\CommentBundleEnhancer
   + */
   

   We are adding @group Drupal these days. I think it just makes sense.

No it will only do it when the bundle is a comment bundle see isset($bundles[$defaults['bundle']])

At least this does not change the bundles variable.

Committed 8caad96 and pushed to 8.x. Thanks!