Issue #3375919 by mondrake, daffie: Deprecate usage of...

Issue #3375919 by mondrake, daffie: Deprecate usage of Connection::getDriverClass for 'Install\Tasks'

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

@@ -900,6 +900,7 @@ protected function expandArguments(&$query, &$args) {
    */
   public function getDriverClass($class) {
     match($class) {
+      'Install\\Tasks',
       'ExceptionHandler',
       'Select',
       'Insert',

core/modules/system/system.install

@@ -555,7 +555,7 @@ function system_requirements($phase) {
 
   if ($phase === 'runtime' || $phase === 'update') {
     // Database information.
-    $class = Database::getConnection()->getDriverClass('Install\\Tasks');
+    $class = Database::getConnection()->getConnectionOptions()['namespace'] . '\\Install\\Tasks';
     /** @var \Drupal\Core\Database\Install\Tasks $tasks */
     $tasks = new $class();
     $requirements['database_system'] = [

core/tests/Drupal/Tests/Core/Database/ConnectionTest.php

@@ -326,6 +326,7 @@ public function testGetDriverClass($expected, $namespace, $class) {
     $mock_pdo = $this->createMock('Drupal\Tests\Core\Database\Stub\StubPDO');
     $connection = new StubConnection($mock_pdo, ['namespace' => $namespace]);
     match($class) {
+      'Install\\Tasks',
       'ExceptionHandler',
       'Select',
       'Insert',