/usr/include/evolution-data-server/libebackend/ is in libebackend1.2-dev 3.22.7-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/evolution-data-server/libebackend/e-backend-enums.h
/usr/include/evolution-data-server/libebackend/e-backend-enumtypes.h
/usr/include/evolution-data-server/libebackend/e-backend-factory.h
/usr/include/evolution-data-server/libebackend/e-backend.h
/usr/include/evolution-data-server/libebackend/e-cache-reaper.h
/usr/include/evolution-data-server/libebackend/e-collection-backend-factory.h
/usr/include/evolution-data-server/libebackend/e-collection-backend.h
/usr/include/evolution-data-server/libebackend/e-data-factory.h
/usr/include/evolution-data-server/libebackend/e-db3-utils.h
/usr/include/evolution-data-server/libebackend/e-dbhash.h
/usr/include/evolution-data-server/libebackend/e-dbus-server.h
/usr/include/evolution-data-server/libebackend/e-file-cache.h
/usr/include/evolution-data-server/libebackend/e-oauth2-support.h
/usr/include/evolution-data-server/libebackend/e-offline-listener.h
/usr/include/evolution-data-server/libebackend/e-server-side-source-credentials-provider.h
/usr/include/evolution-data-server/libebackend/e-server-side-source.h
/usr/include/evolution-data-server/libebackend/e-source-registry-server.h
/usr/include/evolution-data-server/libebackend/e-sqlite3-vfs.h
/usr/include/evolution-data-server/libebackend/e-subprocess-factory.h
/usr/include/evolution-data-server/libebackend/e-user-prompter-server-extension.h
/usr/include/evolution-data-server/libebackend/e-user-prompter-server.h
/usr/include/evolution-data-server/libebackend/e-user-prompter.h
/usr/include/evolution-data-server/libebackend/libebackend.h