MAGETWO-33074: Upgrade response class

 - fix unit tests

Author: okarpenko

dev/tests/integration/framework/Magento/TestFramework/TestCase/AbstractController.php

@@ -142,9 +142,9 @@ public function assertHeaderPcre($headerName, $valueRegex)
         $headerFound = false;
         $headers = $this->getResponse()->getHeaders();
         foreach ($headers as $header) {
-            if ($header['name'] === $headerName) {
+            if ($header->getFieldName() === $headerName) {
                 $headerFound = true;
-                $this->assertRegExp($valueRegex, $header['value']);
+                $this->assertRegExp($valueRegex, $header->getFieldValue());
             }
         }
         if (!$headerFound) {

dev/tests/integration/testsuite/Magento/Catalog/Controller/Adminhtml/Product/Action/AttributeTest.php

@@ -37,7 +37,7 @@ public function testSaveActionRedirectsSuccessfully()
         );
         $isRedirectPresent = false;
         foreach ($this->getResponse()->getHeaders() as $header) {
-            if ($header['name'] === 'Location' && strpos($header['value'], $expectedUrl) === 0) {
+            if ($header->getFieldName() === 'Location' && strpos($header->getFieldValue(), $expectedUrl) === 0) {
                 $isRedirectPresent = true;
             }
         }

dev/tests/integration/testsuite/Magento/Customer/Controller/AccountTest.php

@@ -260,7 +260,7 @@ public function testOpenActionCreatePasswordAction()
         $headers = $this->getResponse()->getHeaders();
         $failed = false;
         foreach ($headers as $header) {
-            if (preg_match('~customer\/account\/login~', $header['value'])) {
+            if (preg_match('~customer\/account\/login~', $header->getFieldValue())) {
                 $failed = true;
                 break;
             }