Update file path for private file. (#1168)
Update file path for private file. (#1168)

Prior to this change, one needed to add `components/Snackbar/src/private` to the list of `include_dirs`.

Closes #1167.
samnm/material-components-ios,chriscox/material-components-ios,brianjmoore/material-components-ios,willlarche/material-components-ios,randallli/material-components-ios,willlarche/material-components-ios,willlarche/material-components-ios,Eccelor/material-components-ios,material-components/material-components-ios,sigito/material-components-ios,randallli/material-components-ios,Eccelor/material-components-ios,sigito/material-components-ios,material-components/material-components-ios,brianjmoore/material-components-ios,samnm/material-components-ios,willlarche/material-components-ios,chriscox/material-components-ios,Eccelor/material-components-ios,material-components/material-components-ios,chriscox/material-components-ios,randallli/material-components-ios,samnm/material-components-ios,sigito/material-components-ios,material-components/material-components-ios,material-components/material-components-ios,brianjmoore/material-components-ios,brianjmoore/material-components-ios,sigito/material-components-ios,willlarche/material-components-ios,Eccelor/material-components-ios,samnm/material-components-ios,chriscox/material-components-ios,randallli/material-components-ios,randallli/material-components-ios,Eccelor/material-components-ios,sigito/material-components-ios,randallli/material-components-ios,chriscox/material-components-ios,samnm/material-components-ios,brianjmoore/material-components-ios