Revert "Fixes issue where the wrong line gets highlighted"

This reverts commit 3364706262.

src/Whoops/Exception/Frame.php

@@ -186,10 +186,7 @@ class Frame implements Serializable
                 $lines = array_slice($lines, $start, $length, true);
             }
 
-            return array_map(function($line)
-            {
-                return empty($line) ? ' ' : $line;
-            }, $lines);
+            return $lines;
         }
     }