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Summary: Closes https://github.com/google/material-components-ios/issues/59

Reviewers: randallli, #material_components_ios_owners

Reviewed By: randallli, #material_components_ios_owners

Subscribers: randallli, featherless

Projects: #material_components_ios

Differential Revision: http://codereview.cc/D112

randallli/material-components-ios,Eccelor/material-components-ios,randallli/material-components-ios,willlarche/material-components-ios,randallli/material-components-ios,material-components/material-components-ios,chriscox/material-components-ios,willlarche/material-components-ios,willlarche/material-components-ios,samnm/material-components-ios,sigito/material-components-ios,Eccelor/material-components-ios,Eccelor/material-components-ios,brianjmoore/material-components-ios,sigito/material-components-ios,material-components/material-components-ios,samnm/material-components-ios,chriscox/material-components-ios,randallli/material-components-ios,sigito/material-components-ios,Eccelor/material-components-ios,willlarche/material-components-ios,randallli/material-components-ios,brianjmoore/material-components-ios,chriscox/material-components-ios,brianjmoore/material-components-ios,brianjmoore/material-components-ios,samnm/material-components-ios,willlarche/material-components-ios,material-components/material-components-ios,sigito/material-components-ios,brianjmoore/material-components-ios,material-components/material-components-ios,Eccelor/material-components-ios,randallli/material-components-ios,sigito/material-components-ios,samnm/material-components-ios,chriscox/material-components-ios,material-components/material-components-ios,samnm/material-components-ios,chriscox/material-components-ios