Register autoloading before running migrations

Signed-off-by: Joas Schilling <coding@schilljs.com>

lib/private/Installer.php

 	public static function installShippedApp($app) {
 		//install the database
 		$appPath = OC_App::getAppPath($app);
+		\OC_App::registerAutoloading($app, $appPath);
+
 		if(is_file("$appPath/appinfo/database.xml")) {
 			try {
 				OC_DB::createDbFromStructure("$appPath/appinfo/database.xml");
 		}
 
 		//run appinfo/install.php
-		\OC_App::registerAutoloading($app, $appPath);
 		self::includeAppScript("$appPath/appinfo/install.php");
 
 		$info = OC_App::getAppInfo($app);

lib/private/legacy/app.php

 		if($appPath === false) {
 			return false;
 		}
+		self::registerAutoloading($appId, $appPath);
+
 		$appData = self::getAppInfo($appId);
 		self::executeRepairSteps($appId, $appData['repair-steps']['pre-migration']);
 
 			self::loadApp($appId);
 			include $appPath . '/appinfo/update.php';
 		}
-		self::registerAutoloading($appId, $appPath);
 		self::setupBackgroundJobs($appData['background-jobs']);
 		if(isset($appData['settings']) && is_array($appData['settings'])) {
 			\OC::$server->getSettingsManager()->setupSettings($appData['settings']);