WARNING on line 2, column 14 of spec/libsass-issues/issue_1305-3.5/input.scss: 
DEPRECATION WARNING: Passing a string to call() is deprecated and will be illegal
in Sass 4.0. Use call(get-function("unquote")) instead.
    content: call('unquote', 'foo', ()...);
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
