Merge "VintfObject: use toXml." am: e8456d8ded am: c3a768efaf am: 4d601b8a2e

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1678425

Change-Id: I60f9090bf4c9f0014b56feb1a14aa96b6ec7a84e