Merge "KeyMint VTS: catch empty cert chains" am: 38fe3c5962 am: 675972efc4 am: 9e1c4c1486

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1787827

Change-Id: I1aeefad9c1ebc54308a994a2b086d4e4aa2c4c63