diff --git a/core/lib/Drupal/Core/Routing/UrlGenerator.php b/core/lib/Drupal/Core/Routing/UrlGenerator.php
index c9521ed..b535777 100644
--- a/core/lib/Drupal/Core/Routing/UrlGenerator.php
+++ b/core/lib/Drupal/Core/Routing/UrlGenerator.php
@@ -298,7 +298,7 @@ public function generateFromRoute($name, $parameters = array(), $options = array
 
     // Generate a relative URL having no path, just query string and fragment.
     if ($route->getOption('_no_path')) {
-      $query = $query_params ? '?' . UrlHelper::buildQuery($query_params) : '';
+      $query = $query_params ? '?' . http_build_query($query_params, '', '&') : '';
       $url = $query . $fragment;
       return $collect_bubbleable_metadata ? $generated_url->setGeneratedUrl($url) : $url;
     }
diff --git a/core/modules/statistics/src/Tests/StatisticsReportsTest.php b/core/modules/statistics/src/Tests/StatisticsReportsTest.php
index 2dbfa8d..f2a79ff 100644
--- a/core/modules/statistics/src/Tests/StatisticsReportsTest.php
+++ b/core/modules/statistics/src/Tests/StatisticsReportsTest.php
@@ -6,7 +6,6 @@
  */
 
 namespace Drupal\statistics\Tests;
-use Drupal\Component\Utility\UrlHelper;
 
 /**
  * Tests display of statistics report blocks.
@@ -27,7 +26,7 @@ function testPopularContentBlock() {
     $this->drupalGet('node/' . $node->id());
     // Manually calling statistics.php, simulating ajax behavior.
     $nid = $node->id();
-    $post = UrlHelper::buildQuery(array('nid' => $nid));
+    $post = http_build_query(array('nid' => $nid));
     $headers = array('Content-Type' => 'application/x-www-form-urlencoded');
     global $base_url;
     $stats_path = $base_url . '/' . drupal_get_path('module', 'statistics'). '/statistics.php';
diff --git a/core/modules/statistics/src/Tests/StatisticsTokenReplaceTest.php b/core/modules/statistics/src/Tests/StatisticsTokenReplaceTest.php
index 9de2959..792c40a 100644
--- a/core/modules/statistics/src/Tests/StatisticsTokenReplaceTest.php
+++ b/core/modules/statistics/src/Tests/StatisticsTokenReplaceTest.php
@@ -7,8 +7,6 @@
 
 namespace Drupal\statistics\Tests;
 
-use Drupal\Component\Utility\UrlHelper;
-
 /**
  * Generates text using placeholders for dummy content to check statistics token
  * replacement.
@@ -31,7 +29,7 @@ function testStatisticsTokenReplacement() {
     $this->drupalGet('node/' . $node->id());
     // Manually calling statistics.php, simulating ajax behavior.
     $nid = $node->id();
-    $post = UrlHelper::buildQuery(array('nid' => $nid));
+    $post = http_build_query(array('nid' => $nid));
     $headers = array('Content-Type' => 'application/x-www-form-urlencoded');
     global $base_url;
     $stats_path = $base_url . '/' . drupal_get_path('module', 'statistics'). '/statistics.php';
diff --git a/core/modules/system/src/Tests/Common/UrlTest.php b/core/modules/system/src/Tests/Common/UrlTest.php
index 3c43406..f52d022 100644
--- a/core/modules/system/src/Tests/Common/UrlTest.php
+++ b/core/modules/system/src/Tests/Common/UrlTest.php
@@ -313,12 +313,12 @@ function testExternalUrls() {
     $url = $test_url;
     $query = array($this->randomMachineName(5) => $this->randomMachineName(5));
     $result = Url::fromUri($url, array('query' => $query))->toString();
-    $this->assertEqual($url . '?' . UrlHelper::buildQuery($query), $result, 'External URL can be extended with a query string in $options.');
+    $this->assertEqual($url . '?' . http_build_query($query, '', '&'), $result, 'External URL can be extended with a query string in $options.');
 
     // Verify query string can be extended in an external URL.
     $url = $test_url . '?drupal=awesome';
     $query = array($this->randomMachineName(5) => $this->randomMachineName(5));
     $result = Url::fromUri($url, array('query' => $query))->toString();
-    $this->assertEqual($url . '&' . UrlHelper::buildQuery($query), $result);
+    $this->assertEqual($url . '&' . http_build_query($query, '', '&'), $result);
   }
 }