Merge "Add marshal() and unmarshal() APIs." am: cf2e66bf19 am: af8f9d666c am: 401f796fb8 am: b19e7d7b49

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/1809496

Change-Id: Iacbf958c3cb39c0ea9c014af81b6ac85823779d7