commit 82e1b8d96ce0105198a5244442d62df375ec7ce2
Author: Pieter Frenssen <pieter@frenssen.be>
Date:   Sat Jul 4 15:08:46 2015 +0200

    23

diff --git a/core/lib/Drupal/Core/Cache/RuntimeCacheContextDependencyInterface.php b/core/lib/Drupal/Core/Cache/RuntimeCacheableDependencyInterface.php
similarity index 35%
rename from core/lib/Drupal/Core/Cache/RuntimeCacheContextDependencyInterface.php
rename to core/lib/Drupal/Core/Cache/RuntimeCacheableDependencyInterface.php
index 1c84991..03d88d4 100644
--- a/core/lib/Drupal/Core/Cache/RuntimeCacheContextDependencyInterface.php
+++ b/core/lib/Drupal/Core/Cache/RuntimeCacheableDependencyInterface.php
@@ -2,17 +2,17 @@
 
 /**
  * @file
- * Contains \Drupal\Core\Cache\RuntimeCacheContextDependencyInterface.
+ * Contains \Drupal\Core\Cache\RuntimeCacheableDependencyInterface.
  */
 
 namespace Drupal\Core\Cache;
 
 /**
- * Defines an interface for objects that can add cache contexts during runtime.
+ * Interface for objects that can change cache dependencies during runtime.
  *
  * @ingroup cache
  */
-interface RuntimeCacheContextDependencyInterface {
+interface RuntimeCacheableDependencyInterface {
 
   /**
    * Adds cache contexts during runtime.
@@ -22,4 +22,20 @@
    */
   public function addRuntimeCacheContexts(array $cache_contexts);
 
+  /**
+   * Adds cache tags during runtime.
+   *
+   * @param string[] $cache_tags
+   *   An array of cache tags to add.
+   */
+  public function addRuntimeCacheTags(array $cache_tags);
+
+  /**
+   * Sets the cache max age during runtime.
+   *
+   * @param int $max_age
+   *   The cache max-age value.
+   */
+  public function setRuntimeCacheMaxAge($max_age);
+
 }
diff --git a/core/lib/Drupal/Core/Config/ConfigBase.php b/core/lib/Drupal/Core/Config/ConfigBase.php
index 9fc9cdf..556926d 100644
--- a/core/lib/Drupal/Core/Config/ConfigBase.php
+++ b/core/lib/Drupal/Core/Config/ConfigBase.php
@@ -11,7 +11,7 @@
 use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheableDependencyInterface;
-use Drupal\Core\Cache\RuntimeCacheContextDependencyInterface;
+use Drupal\Core\Cache\RuntimeCacheableDependencyInterface;
 use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
 
 /**
@@ -29,7 +29,7 @@
  * @see \Drupal\Core\Config\Config
  * @see \Drupal\Core\Theme\ThemeSettings
  */
-abstract class ConfigBase implements CacheableDependencyInterface, RuntimeCacheContextDependencyInterface {
+abstract class ConfigBase implements CacheableDependencyInterface, RuntimeCacheableDependencyInterface {
   use DependencySerializationTrait;
 
   /**
@@ -49,11 +49,25 @@
   /**
    * The cache contexts this configuration object provides.
    *
-   * @var array
+   * @var string[]
    */
   protected $cacheContexts = [];
 
   /**
+   * The cache tags this configuration object provides.
+   *
+   * @var string[]
+   */
+  protected $cacheTags = [];
+
+  /**
+   * The cache max age this configuration object provides.
+   *
+   * @var int
+   */
+  protected $cacheMaxAge;
+
+  /**
    * The maximum length of a configuration object name.
    *
    * Many filesystems (including HFS, NTFS, and ext4) have a maximum file name
@@ -301,4 +315,18 @@ public function addRuntimeCacheContexts(array $cache_contexts) {
     $this->cacheContexts = Cache::mergeContexts($this->cacheContexts, $cache_contexts);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function addRuntimeCacheTags(array $cache_tags) {
+    $this->cacheTags = Cache::mergeTags($this->cacheTags, $cache_tags);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setRuntimeCacheMaxAge($max_age) {
+    $this->cacheMaxAge = Cache::mergeMaxAges($this->cacheMaxAge, $max_age);
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Config/ConfigFactory.php b/core/lib/Drupal/Core/Config/ConfigFactory.php
index fdec551..61328a2 100644
--- a/core/lib/Drupal/Core/Config/ConfigFactory.php
+++ b/core/lib/Drupal/Core/Config/ConfigFactory.php
@@ -10,7 +10,7 @@
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\Context\CacheContextInterface;
-use Drupal\Core\Cache\RuntimeCacheContextDependencyInterface;
+use Drupal\Core\Cache\RuntimeCacheableDependencyInterface;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
@@ -130,7 +130,7 @@ protected function doGet($name, $immutable = TRUE) {
       }
 
       // Propagate cache contexts to the config object.
-      $this->cache[$cache_key]->addRuntimeCacheContexts($this->loadCacheContextOverrides());
+      $this->propagateCacheableDependencyOverrides($cache_key);
 
       return $this->cache[$cache_key];
     }
@@ -190,8 +190,8 @@ protected function doLoadMultiple(array $names, $immutable = TRUE) {
           }
         }
 
-        // Propagate cache contexts to the config object.
-        $this->cache[$cache_key]->addRuntimeCacheContexts($this->loadCacheContextOverrides());
+        // Propagate cacheable dependencies to the config object.
+        $this->propagateCacheableDependencyOverrides($cache_key);
 
         $list[$name] = $this->cache[$cache_key];
       }
@@ -220,17 +220,21 @@ protected function loadOverrides(array $names) {
   }
 
   /**
-   * Get arbitrary cache context overrides.
+   * Propagates overridden cacheable dependencies to cached config objects.
    *
-   * @return array
-   *   An array of cache context tokens.
+   * @param string $cache_key
+   *   The key of the cached config object to update.
    */
-  protected function loadCacheContextOverrides() {
-    $overrides = [];
+  protected function propagateCacheableDependencyOverrides($cache_key) {
+    $overrides = ['contexts' => [], 'tags' => [], 'max_age' => Cache::PERMANENT];
     foreach ($this->configFactoryOverrides as $override) {
-      $overrides = Cache::mergeContexts($overrides, $override->getCacheContexts());
+      $overrides['contexts'] = Cache::mergeContexts($overrides['contexts'], $override->getCacheContexts());
+      $overrides['tags'] = Cache::mergeTags($overrides['tags'], $override->getCacheTags());
+      $overrides['max_age'] = Cache::mergeMaxAges($overrides['max_age'], $override->getCacheMaxAge());
     }
-    return $overrides;
+    $this->cache[$cache_key]->addRuntimeCacheContexts($overrides['contexts']);
+    $this->cache[$cache_key]->addRuntimeCacheTags($overrides['tags']);
+    $this->cache[$cache_key]->setRuntimeCacheMaxAge($overrides['max_age']);
   }
 
   /**