diff -u b/core/includes/common.inc b/core/includes/common.inc
--- b/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -4801,7 +4801,7 @@
  */
 function _drupal_flush_css_js() {
   // The timestamp is converted to base 36 in order to make it more compact.
-  Drupal::state()->set('system.css_js_query_string', base_convert(REQUEST_TIME, 10, 36));
+  variable_set('css_js_query_string', base_convert(REQUEST_TIME, 10, 36));
 }
 
 /**
@@ -4845,7 +4845,7 @@
  */
 function _drupal_flush_css_js() {
   // The timestamp is converted to base 36 in order to make it more compact.
-  variable_set('css_js_query_string', base_convert(REQUEST_TIME, 10, 36));
+  Drupal::state()->set('system.css_js_query_string', base_convert(REQUEST_TIME, 10, 36));
 }
 
 /**
diff -u b/core/lib/Drupal/Core/Asset/CssCollectionRenderer.php b/core/lib/Drupal/Core/Asset/CssCollectionRenderer.php
--- b/core/lib/Drupal/Core/Asset/CssCollectionRenderer.php
+++ b/core/lib/Drupal/Core/Asset/CssCollectionRenderer.php
@@ -7,6 +7,7 @@
 namespace Drupal\Core\Asset;
 
 use Drupal\Core\Asset\AssetCollectionRendererInterface;
+use Drupal\Core\KeyValueStore\KeyValueStoreInterface;
 use Drupal\Component\Utility\String;
 
 /**
@@ -15,6 +16,23 @@
 class CssCollectionRenderer implements AssetCollectionRendererInterface {
 
   /**
+   * The state key/value store.
+   *
+   * @var \Drupal\Core\KeyValueStore\KeyValueStoreInterface
+   */
+  protected $state;
+
+  /**
+   * Constructs a CssCollectionRenderer.
+   *
+   * @param \Drupal\Core\KeyValueStore\KeyValueStoreInterface
+   *   The state key/value store.
+   */
+  public function __construct(KeyValueStoreInterface $state) {
+    $this->state = $state;
+  }
+
+  /**
    * {@inheritdoc}
    */
   public function render(array $css_assets) {
@@ -24,7 +42,7 @@
     // browser-caching. The string changes on every update or full cache
     // flush, forcing browsers to load a new copy of the files, as the
     // URL changed.
-    $query_string = \Drupal::state()->get('system.css_js_query_string') ?: '0';
+    $query_string = $this->state->get('system.css_js_query_string') ?: '0';
 
     // Defaults for LINK and STYLE elements.
     $link_element_defaults = array(
diff -u b/core/lib/Drupal/Core/Asset/JsCollectionRenderer.php b/core/lib/Drupal/Core/Asset/JsCollectionRenderer.php
--- b/core/lib/Drupal/Core/Asset/JsCollectionRenderer.php
+++ b/core/lib/Drupal/Core/Asset/JsCollectionRenderer.php
@@ -1,6 +1,5 @@
 <?php
 
-
 /**
  * Contains \Drupal\Core\Asset\JsCollectionRenderer.
  */
only in patch2:
unchanged:
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -619,6 +619,7 @@ services:
     scope: request
   asset.css.collection_renderer:
     class: Drupal\Core\Asset\CssCollectionRenderer
+    arguments: [ '@state' ]
   asset.css.collection_optimizer:
     class: Drupal\Core\Asset\CssCollectionOptimizer
     arguments: [ '@asset.css.collection_grouper', '@asset.css.optimizer', '@asset.css.dumper', '@state' ]
only in patch2:
unchanged:
--- a/core/tests/Drupal/Tests/Core/Asset/CssCollectionRendererUnitTest.php
+++ b/core/tests/Drupal/Tests/Core/Asset/CssCollectionRendererUnitTest.php
@@ -71,6 +71,13 @@ class CssCollectionRendererUnitTest extends UnitTestCase {
    */
   protected $inline_css_group;
 
+  /**
+   * The state mock class.
+   *
+   * @var \Drupal\Core\KeyValueStore\KeyValueStoreInterface|\PHPUnit_Framework_MockObject_MockObject
+   */
+  protected $state;
+
   public static function getInfo() {
     return array(
       'name' => 'CSS asset collection renderer functionality',
@@ -82,7 +89,9 @@ public static function getInfo() {
   function setUp() {
     parent::setUp();
 
-    $this->renderer = new CssCollectionRenderer();
+    $this->state = $this->getMock('Drupal\Core\KeyValueStore\KeyValueStoreInterface');
+
+    $this->renderer = new CssCollectionRenderer($this->state);
     $this->file_css_group = array(
       'group' => -100,
       'every_page' => TRUE,
@@ -540,6 +549,10 @@ function testRenderProvider() {
    * @dataProvider testRenderProvider
    */
   function testRender(array $css_assets, array $render_elements) {
+    $this->state->expects($this->once())
+      ->method('get')
+      ->with('system.css_js_query_string')
+      ->will($this->returnValue(NULL));
     $this->assertSame($render_elements, $this->renderer->render($css_assets));
   }
 
@@ -547,6 +560,10 @@ function testRender(array $css_assets, array $render_elements) {
    * Tests a CSS asset group with the invalid 'type' => 'internal'.
    */
   function testRenderInvalidType() {
+    $this->state->expects($this->once())
+      ->method('get')
+      ->with('system.css_js_query_string')
+      ->will($this->returnValue(NULL));
     $this->setExpectedException('Exception', 'Invalid CSS asset type.');
 
     $css_group = array(