MAGETWO-58174: When catalog is being indexed it should index in place or leverage an index alias so store can still function during a long index run

  - Use ::class instead of string

Author: igrybkov

dev/tests/integration/testsuite/Magento/CatalogSearch/Model/Indexer/SwitcherUsedInFulltextTest.php

@@ -81,10 +81,10 @@ protected function setUp()
 
         $objectManager->configure(
             [
-                'Magento\CatalogSearch\Model\Indexer\Fulltext' => [
+                ltrim(\Magento\CatalogSearch\Model\Indexer\Fulltext::class, '\\') => [
                     'arguments' => [
                         'indexSwitcher' => [
-                            'instance' => 'Magento\CatalogSearch\Model\Indexer\IndexSwitcherMock',
+                            'instance' => ltrim(\Magento\CatalogSearch\Model\Indexer\IndexSwitcherMock::class, '\\'),
                         ],
                     ],
                 ],