route: code layout clean up admin route
test: route: add admin tests defined at r8162
route: code layout clean up mail_handler route
test: route: add mail_handler test defined at r8162
Japanese translation updated by Go MAEDA (#9876)
route: code layout clean up sys route
test: route: add sys test
route: code layout clean up watchers route
test: route: add watchers test defined at r8162
test: route: add search test defined at r8162
