I keep on getting when running grunt build even with a clean Yeoman angular build: yo angular whatever.
Warning: Running "imagemin:dist" (imagemin) task
Fatal error: Cannot read property 'contents' of undefined
just update your grunt-contrib-imagemin version.
Ex: "grunt-contrib-imagemin": "^0.9.2"
to
"grunt-contrib-imagemin": "^1.0.0"
it's work for me.