Issue #3443276 by mondrake: Remove dead code from Connection

core/lib/Drupal/Core/Database/Connection.php

@@ -12,7 +12,6 @@ use Drupal\Core\Database\Query\Merge;
 use Drupal\Core\Database\Query\Select;
 use Drupal\Core\Database\Query\Truncate;
 use Drupal\Core\Database\Query\Update;
-use Drupal\Core\Database\Query\Upsert;
 use Drupal\Core\Database\Transaction\TransactionManagerInterface;
 use Drupal\Core\Pager\PagerManagerInterface;
 
@@ -758,59 +757,7 @@ abstract class Connection {
     };
     if (empty($this->driverClasses[$class])) {
       $driver_class = $this->connectionOptions['namespace'] . '\\' . $class;
-      if (class_exists($driver_class)) {
+      $this->driverClasses[$class] = class_exists($driver_class) ? $driver_class : $class;
-        $this->driverClasses[$class] = $driver_class;
-      }
-      else {
-        switch ($class) {
-          case 'Condition':
-            $this->driverClasses[$class] = Condition::class;
-            break;
-
-          case 'Delete':
-            $this->driverClasses[$class] = Delete::class;
-            break;
-
-          case 'ExceptionHandler':
-            $this->driverClasses[$class] = ExceptionHandler::class;
-            break;
-
-          case 'Insert':
-            $this->driverClasses[$class] = Insert::class;
-            break;
-
-          case 'Merge':
-            $this->driverClasses[$class] = Merge::class;
-            break;
-
-          case 'Schema':
-            $this->driverClasses[$class] = Schema::class;
-            break;
-
-          case 'Select':
-            $this->driverClasses[$class] = Select::class;
-            break;
-
-          case 'Transaction':
-            $this->driverClasses[$class] = Transaction::class;
-            break;
-
-          case 'Truncate':
-            $this->driverClasses[$class] = Truncate::class;
-            break;
-
-          case 'Update':
-            $this->driverClasses[$class] = Update::class;
-            break;
-
-          case 'Upsert':
-            $this->driverClasses[$class] = Upsert::class;
-            break;
-
-          default:
-            $this->driverClasses[$class] = $class;
-        }
-      }
     }
     return $this->driverClasses[$class];
   }