e7c720632acb138118ebada4a3960bcf0d99a46b Fix: -api columns().widths() didn't correctly take into account Responsive hidden columns

More specifically the column `:visible` selector does, but
`columnIndexToVisible` does not, resulting in an index mismatch. The fix
is to stay with just the columns selected.

https://datatables.net/forums/discussion/81795/

Sync to source repo @e7c720632acb138118ebada4a3960bcf0d99a46b

Author: dtbuild

datatables.json

@@ -14,5 +14,5 @@
     ],
     "src-repo": "http://github.com/DataTables/DataTablesSrc",
     "last-tag": "2.3.8",
-    "last-sync": "7e78364360dd57da339ac5e113490c12349a849b"
+    "last-sync": "e7c720632acb138118ebada4a3960bcf0d99a46b"
 }