Keystore 2.0: Implement APC service.

This patch implements the Android Protected Confirmation service in
Keystore 2.0. This includes a C++ wrapper around the HIDL confirmationui
interface which will stay a HIDL interface for now.
This patch also includes the new AIDL specification.

This patch lacks death listener registration b/176491050.

Bug: 159341464
Bug: 173546269
Test: None
Change-Id: Ida4af108e86b538ab64d1dea4809cfa3b36f74cd
13 files changed