Fix constant definition (hechoendrupal#160)

* [console] Remove constants.php file.

* [console] Extend DrupalFinder class.

* [console] Fix docblock.

composer.json

@@ -57,7 +57,6 @@
     "prefer-stable": true,
     "autoload": {
         "files": [
-            "src/constants.php",
             "src/functions.php"
         ],
         "psr-4": {"Drupal\\Console\\Core\\": "src"}

src/Utils/DrupalFinder.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\Console\Core\Utils\DrupalFinder.
+ */
+
+namespace Drupal\Console\Core\Utils;
+
+use DrupalFinder\DrupalFinder as DrupalFinderBase;
+
+/**
+ * Class DrupalFinder
+ *
+ * @package Drupal\Console\Core\Utils
+ */
+class DrupalFinder extends DrupalFinderBase
+{
+    public function locateRoot($start_path)
+    {
+        if (parent::locateRoot($start_path)) {
+            $composerRoot = $this->getComposerRoot();
+            $vendorDir = str_replace(
+                $composerRoot .'/', '', $this->getVendorDir()
+            );
+            if (!defined("DRUPAL_CONSOLE_CORE")) {
+                define(
+                    "DRUPAL_CONSOLE_CORE",
+                    "/{$vendorDir}/drupal/console-core/"
+                );
+            }
+            if (!defined("DRUPAL_CONSOLE")) {
+                define("DRUPAL_CONSOLE", "/{$vendorDir}/drupal/console/");
+            }
+            if (!defined("DRUPAL_CONSOLE_LANGUAGE")) {
+                define(
+                    "DRUPAL_CONSOLE_LANGUAGE",
+                    "/{$vendorDir}/drupal/console-%s/translations/"
+                );
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+}