MAGETWO-43787: cache:clean command doesn't clear Varnish cache

 - use _nosid route param so session does not get invoked when building url

Author: Dale Sikkema

app/code/Magento/PageCache/Model/Cache/Server.php

@@ -60,7 +60,7 @@ public function getUris()
             $httpHost = $this->request->getHttpHost();
             $servers[] = $httpHost ?
                 UriFactory::factory('')->setHost($httpHost)->setPort(self::DEFAULT_PORT)->setScheme('http') :
-                UriFactory::factory($this->urlBuilder->getUrl('*'))
+                UriFactory::factory($this->urlBuilder->getUrl('*', ['_nosid' => true])) // Don't use SID in building URL
                     ->setScheme('http')
                     ->setPath(null)
                     ->setQuery(null);

app/code/Magento/PageCache/Test/Unit/Model/Cache/ServerTest.php

@@ -64,7 +64,7 @@ public function testGetUris(
             ->willReturn($httpHost);
         $this->urlBuilderMock->expects($this->exactly($getUrlCallCtr))
             ->method('getUrl')
-            ->with('*')
+            ->with('*', ['_nosid' => true])
             ->willReturn($url);
 
         $uris = [];