Fix constant accessor

Author: driesvints

Response.php

@@ -949,7 +949,7 @@ public function setEtag(string $etag = null, bool $weak = false): object
      */
     public function setCache(array $options): object
     {
-        if ($diff = array_diff(array_keys($options), array_keys(static::HTTP_RESPONSE_CACHE_CONTROL_DIRECTIVES))) {
+        if ($diff = array_diff(array_keys($options), array_keys(self::HTTP_RESPONSE_CACHE_CONTROL_DIRECTIVES))) {
             throw new \InvalidArgumentException(sprintf('Response does not support the following options: "%s".', implode('", "', $diff)));
         }
 

Tests/ResponseTest.php

@@ -672,6 +672,12 @@ public function testSetCache()
 
             $this->assertFalse($response->headers->hasCacheControlDirective(str_replace('_', '-', $directive)));
         }
+
+        $response = new DefaultResponse();
+
+        $options = ['etag' => '"whatever"'];
+        $response->setCache($options);
+        $this->assertSame($response->getEtag(), '"whatever"');
     }
 
     public function testSendContent()