massive backups in access to GfeScript instance map.
Issue #361: Further modifications to GfeScriptExecutor and GfeScript to improve synchronization-caused back-logs.
Change-Id: Ic33ef5e62d2bd1e19dd2cfedcfefe050cf7efe9e
Former-commit-id: 679996850315f699d47633da5baf593c72ba7927