Merge branch 'hotfix/3011' into develop

Close zendframework/zendframework#3011

src/Server/Response.php

@@ -118,10 +118,10 @@ public function getResult()
     /**
      * Set result error
      *
-     * @param  Error $error
+     * @param  mixed $error
      * @return Response
      */
-    public function setError(Error $error)
+    public function setError(Error $error = null)
     {
         $this->error = $error;
         return $this;

test/Server/ResponseTest.php

@@ -67,6 +67,13 @@ public function testShouldBeAbleToRetrieveErrorObject()
         $this->assertSame($error, $this->response->getError());
     }
 
+    public function testErrorAccesorsShouldWorkWithNullInput()
+    {
+        $this->response->setError(null);
+        $this->assertNull($this->response->getError());
+        $this->assertFalse($this->response->isError());
+    }
+
     public function testIdShouldBeNullByDefault()
     {
         $this->assertNull($this->response->getId());