minor #1194 PHPDocs Application -> HttpKernelInterface (SpacePossum)

This PR was merged into the 1.3 branch.

Discussion
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PHPDocs Application -> HttpKernelInterface

replacement of https://github.com/silexphp/Silex/pull/1193
(could not reopen that one because of a forced push)

Commits
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b960bad3 PHPDocs Application -> HttpKernelInterface

src/Silex/WebTestCase.php

@@ -12,7 +12,7 @@
 namespace Silex;
 
 use Symfony\Component\HttpKernel\Client;
-use Symfony\Component\HttpKernel\HttpKernel;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
 
 /**
  * WebTestCase is the base class for functional tests.
@@ -22,9 +22,9 @@ use Symfony\Component\HttpKernel\HttpKernel;
 abstract class WebTestCase extends \PHPUnit_Framework_TestCase
 {
     /**
-     * Application instance.
+     * HttpKernelInterface instance.
      *
-     * @var Application
+     * @var HttpKernelInterface
      */
     protected $app;
 
@@ -42,14 +42,14 @@ abstract class WebTestCase extends \PHPUnit_Framework_TestCase
     /**
      * Creates the application.
      *
-     * @return HttpKernel
+     * @return HttpKernelInterface
      */
     abstract public function createApplication();
 
     /**
      * Creates a Client.
      *
-     * @param array $server An array of server parameters
+     * @param array $server Server parameters
      *
      * @return Client A Client instance
      */