ipphelper: initialize mediaReadySet am: a9cc00dd16 am: 08d50cfdf0 am: 5eac40aa61 am: 30d6de3269

Original change: https://android-review.googlesource.com/c/platform/packages/services/BuiltInPrintService/+/1684596

Change-Id: I15e9340f22bd2819dd3497a8e44a88250d698ea2