Summary: Part of #24875 ## Changelog [General] [Added] - add TM spec for DevLoadingView Pull Request resolved: https://github.com/facebook/react-native/pull/24930 Reviewed By: RSNara Differential Revision: D15423524 Pulled By: fkgozali fbshipit-source-id: 18ca65abcd4fb3c0ec0434ccba0c0e1d97c17995