MAGETWO-39777: [IE] PayPal Express Checkout is always displayed as disabled

- fix for Payflow Config class

Author: Yushkin, Dmytro

app/code/Magento/Paypal/Model/AbstractConfig.php

@@ -47,7 +47,7 @@ abstract class AbstractConfig implements ConfigInterface
     /**
      * @var string
      */
-    private $pathPattern;
+    protected $pathPattern;
 
     /**
      * @param \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig

app/code/Magento/Paypal/Model/PayflowConfig.php

@@ -11,7 +11,7 @@
  * Class PayflowConfig
  * @todo ELiminate current configuration class
  */
-class PayflowConfig extends AbstractConfig
+class PayflowConfig extends Config
 {
     /**#@-*/
 
@@ -89,4 +89,19 @@ public function isMethodActive($method)
         return parent::isMethodActive(Config::METHOD_PAYMENT_PRO)
             || parent::isMethodActive(Config::METHOD_PAYFLOWPRO);
     }
+
+    /**
+     * Map any supported payment method into a config path by specified field name
+     *
+     * @param string $fieldName
+     * @return string|null
+     */
+    protected function _getSpecificConfigPath($fieldName)
+    {
+        if ($this->pathPattern) {
+            return sprintf($this->pathPattern, $this->_methodCode, $fieldName);
+        }
+
+        return "payment/{$this->_methodCode}/{$fieldName}";
+    }
 }

app/code/Magento/Paypal/Test/Unit/Model/PayflowConfigTest.php

@@ -6,6 +6,7 @@
 namespace Magento\Paypal\Test\Unit\Model;
 
 use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;
 use Magento\Paypal\Model\PayflowConfig;
 use Magento\Payment\Model\MethodInterface;
 use Magento\Payment\Model\Method\AbstractMethod;
@@ -41,7 +42,14 @@ protected function setUp()
         $this->methodInterfaceMock = $this->getMockBuilder('Magento\Payment\Model\MethodInterface')
             ->getMockForAbstractClass();
 
-        $this->config = new PayflowConfig($this->scopeConfigMock);
+        $om = new ObjectManager($this);
+        $this->config = $om->getObject(
+            'Magento\Paypal\Model\PayflowConfig',
+            [
+                'scopeConfig' => $this->scopeConfigMock,
+            ]
+        );
+//        $this->config = new PayflowConfig($this->scopeConfigMock);
     }
 
     /**
@@ -163,6 +171,11 @@ public function testIsMethodActive(array $expectsMethods, $currentMethod, $resul
     {
         $this->config->setStoreId(5);
 
+        $this->scopeConfigMock->expects($this->any())
+            ->method('getValue')
+            ->with('paypal/general/merchant_country')
+            ->will($this->returnValue('US'));
+
         $i = 0;
         foreach ($expectsMethods as $method => $isActive) {
             $this->scopeConfigMock->expects($this->at($i++))