.../Drupal/Core/Render/PlaceholderGenerator.php    | 12 ++++++++++
 .../Core/Render/PlaceholderGeneratorInterface.php  | 11 +++++++++
 .../Core/Render/PlaceholderingRenderCache.php      | 26 ++++------------------
 core/lib/Drupal/Core/Render/Renderer.php           |  2 +-
 4 files changed, 28 insertions(+), 23 deletions(-)

diff --git a/core/lib/Drupal/Core/Render/PlaceholderGenerator.php b/core/lib/Drupal/Core/Render/PlaceholderGenerator.php
index eeeaf24..dc85f93 100644
--- a/core/lib/Drupal/Core/Render/PlaceholderGenerator.php
+++ b/core/lib/Drupal/Core/Render/PlaceholderGenerator.php
@@ -37,6 +37,18 @@ public function __construct(array $renderer_config) {
   /**
    * {@inheritdoc}
    */
+  public function canCreatePlaceholder(array $element) {
+    return
+      // If generated by a #lazy_builder callback, placeholdering is possible.
+      isset($element['#lazy_builder'])
+      &&
+      // If #create_placeholder === FALSE, placeholdering is disallowed.
+      (!isset($element['#create_placeholder']) || $element['#create_placeholder'] !== FALSE);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function shouldAutomaticallyPlaceholder(array $element) {
     $conditions = $this->rendererConfig['auto_placeholder_conditions'];
 
diff --git a/core/lib/Drupal/Core/Render/PlaceholderGeneratorInterface.php b/core/lib/Drupal/Core/Render/PlaceholderGeneratorInterface.php
index eb96673..df9034d 100644
--- a/core/lib/Drupal/Core/Render/PlaceholderGeneratorInterface.php
+++ b/core/lib/Drupal/Core/Render/PlaceholderGeneratorInterface.php
@@ -15,6 +15,17 @@
 interface PlaceholderGeneratorInterface {
 
   /**
+   * Analyzes whether the given render array can be placeholdered.
+   *
+   * @param array $element
+   *   A render array. Its #lazy_builder and #create_placeholder properties are
+   *   analyzed.
+   *
+   * @return bool
+   */
+  public function canCreatePlaceholder(array $element);
+
+  /**
    * Whether the given render array should be automatically placeholdered.
    *
    * @param array $element
diff --git a/core/lib/Drupal/Core/Render/PlaceholderingRenderCache.php b/core/lib/Drupal/Core/Render/PlaceholderingRenderCache.php
index 0e3adfe..8f3ff6e 100644
--- a/core/lib/Drupal/Core/Render/PlaceholderingRenderCache.php
+++ b/core/lib/Drupal/Core/Render/PlaceholderingRenderCache.php
@@ -92,8 +92,8 @@ public function get(array $elements) {
       return FALSE;
     }
     else {
-      if ($this->canCreatePlaceholder($elements) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($cached_element)) {
-        return $this->createPlaceholder($elements);
+      if ($this->placeholderGenerator->canCreatePlaceholder($elements) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($cached_element)) {
+        return $this->placeholderGenerator->createPlaceholder($elements);
       }
 
       // PlaceholderingRenderCache::set() has cached a bubbled max-age = 0, and
@@ -128,7 +128,7 @@ public function set(array &$elements, array $pre_bubbling_elements) {
     // a #lazy_builder callback.
     // Note: we can permanently cache the fact that this element's subtree
     // resulted in a bubbled max-age=0, because cache context variations
-    if ($result === FALSE && $this->canCreatePlaceholder($pre_bubbling_elements) && $this->requestStack->getCurrentRequest()->isMethodSafe() && !$this->maxAgeAllowsCaching($elements) && $this->maxAgeAllowsCaching($pre_bubbling_elements) && $cid = $this->createCacheID($elements)) {
+    if ($result === FALSE && $this->placeholderGenerator->canCreatePlaceholder($pre_bubbling_elements) && $this->requestStack->getCurrentRequest()->isMethodSafe() && !$this->maxAgeAllowsCaching($elements) && $this->maxAgeAllowsCaching($pre_bubbling_elements) && $cid = $this->createCacheID($elements)) {
       // Cache #cache['max-age'] = 0! We just want to cache the cacheability.
       $data = ['#cache' => $elements['#cache'], '#markup' => '', '#attached' => []];
 
@@ -138,7 +138,7 @@ public function set(array &$elements, array $pre_bubbling_elements) {
       $this->expireOverride = FALSE;
     }
 
-    if ($this->canCreatePlaceholder($pre_bubbling_elements) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($elements)) {
+    if ($this->placeholderGenerator->canCreatePlaceholder($pre_bubbling_elements) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($elements)) {
       // Overwrite $elements with a placeholder. The Renderer (which called this
       // method) will update the context with the bubbleable metadata of the
       // overwritten $elements.
@@ -160,22 +160,4 @@ protected function maxAgeToExpire($max_age) {
     return parent::maxAgeToExpire($max_age);
   }
 
-  /**
-   * Analyzes whether the given render array can be placeholdered.
-   *
-   * @param array $element
-   *   A render array. Its #lazy_builder and #create_placeholder properties are
-   *   analyzed.
-   *
-   * @return bool
-   */
-  protected function canCreatePlaceholder(array $element) {
-    return
-      // If generated by a #lazy_builder callback, placeholdering is possible.
-      isset($element['#lazy_builder'])
-      &&
-      // If #create_placeholder === FALSE, placeholdering is disallowed.
-      (!isset($element['#create_placeholder']) || $element['#create_placeholder'] !== FALSE);
-  }
-
 }
diff --git a/core/lib/Drupal/Core/Render/Renderer.php b/core/lib/Drupal/Core/Render/Renderer.php
index 0981a98..c7ec3b9 100644
--- a/core/lib/Drupal/Core/Render/Renderer.php
+++ b/core/lib/Drupal/Core/Render/Renderer.php
@@ -352,7 +352,7 @@ protected function doRender(&$elements, $is_root_call = FALSE) {
       }
     }
     // Determine whether to do auto-placeholdering.
-    if (isset($elements['#lazy_builder']) && (!isset($elements['#create_placeholder']) || $elements['#create_placeholder'] !== FALSE) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($elements)) {
+    if ($this->placeholderGenerator->canCreatePlaceholder($elements) && $this->placeholderGenerator->shouldAutomaticallyPlaceholder($elements)) {
       $elements['#create_placeholder'] = TRUE;
     }
     // If instructed to create a placeholder, and a #lazy_builder callback is