Allow multiple Google Drive and Dropbox external storages to be configured

apps/files_external/js/dropbox.js

@@ -23,7 +23,6 @@ $(document).ready(function() {
 					});
 				}
 			}
-			return false;
 		}
 	});
 

apps/files_external/js/google.js

@@ -24,7 +24,6 @@ $(document).ready(function() {
 					});
 				}
 			}
-			return false;
 		}
 	});