Clean up entry point generation script. The main refactor from this change is to replace statements like this: decls, defs, export_defs, _, _, _, _ = get_entry_points( apis.EGL, eglxml.all_commands, egl_version_commands, False, egl_param_types, cmd_packed_egl_enums, EGL_PACKED_TYPES, egl_ep_to_object, TEMPLATE_EGL_ENTRY_POINT_EXPORT) With statements like this: eps = EGLEntryPoints(eglxml, egl_version_commands) This will make the script easier to maintain and extend. Bug: angleproject:5653 Change-Id: Ibd0930d45b8629702b7782f43a2d7ebfa4dac9b8 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2705156 Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>