Enable cpp support for IPowerStats AIDL interface am: 5aae5cb79d am: 6e92dab27b am: d43cbbee5f

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1628872

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I2e4dbe6e7a668878434be9dcc2f1b2940e2abeb3