5e4e9003024ed6d4d06562b6f5b86547f735b98c Fix: IE8 was throwing an error due to .return

DD-2735
https://datatables.net/forums/discussion/77489

5eef6ac27017199c44af891b6744d1aa916c7231 Fix: Processing indicator needs a z-index when scrolling enabled

47d6f7293e7d6e14fda932f00c5bcc4fb6925bcb Merge branch 'master' of github.com:DataTables/DataTablesSrc

Sync to source repo @47d6f7293e7d6e14fda932f00c5bcc4fb6925bcb

Author: AllanJard

css/dataTables.bootstrap4.css

@@ -110,6 +110,7 @@ div.dataTables_processing {
   margin-top: -26px;
   text-align: center;
   padding: 2px;
+  z-index: 10;
 }
 div.dataTables_processing > div:last-child {
   position: relative;