identity: Add multi-document presentation support.

This new IPresentationSession interface enables an application to do a
multi-document presentation, something which isn't possible with the
existing API. As a practical example of this consider presenting both
your Mobile Driving License and your Vaccination Certificate in a single
transaction.

Bug: 197965513
Test: New CTS tests and new screen in CtsVerifier
Change-Id: I11712dca35df7f1224debf454731bc17ea9bfb37
diff --git a/identity/aidl/default/common/IdentityCredential.h b/identity/aidl/default/common/IdentityCredential.h
index ef9d133..2935fb8 100644
--- a/identity/aidl/default/common/IdentityCredential.h
+++ b/identity/aidl/default/common/IdentityCredential.h
@@ -30,6 +30,7 @@
 #include <cppbor.h>
 
 #include "IdentityCredentialStore.h"
+#include "PresentationSession.h"
 #include "SecureHardwareProxy.h"
 
 namespace aidl::android::hardware::identity {
@@ -46,11 +47,11 @@
 class IdentityCredential : public BnIdentityCredential {
   public:
     IdentityCredential(sp<SecureHardwareProxyFactory> hwProxyFactory,
-                       sp<SecureHardwarePresentationProxy> hwProxy,
-                       const vector<uint8_t>& credentialData)
+                       const vector<uint8_t>& credentialData,
+                       std::shared_ptr<PresentationSession> session)
         : hwProxyFactory_(hwProxyFactory),
-          hwProxy_(hwProxy),
           credentialData_(credentialData),
+          session_(std::move(session)),
           numStartRetrievalCalls_(0),
           expectedDeviceNameSpacesSize_(0) {}
 
@@ -94,10 +95,13 @@
                                               bool includeChallenge,
                                               vector<uint8_t>* outProofOfDeletionSignature);
 
+    // Creates and initializes hwProxy_.
+    ndk::ScopedAStatus ensureHwProxy();
+
     // Set by constructor
     sp<SecureHardwareProxyFactory> hwProxyFactory_;
-    sp<SecureHardwarePresentationProxy> hwProxy_;
     vector<uint8_t> credentialData_;
+    shared_ptr<PresentationSession> session_;
     int numStartRetrievalCalls_;
 
     // Set by initialize()
@@ -105,6 +109,9 @@
     bool testCredential_;
     vector<uint8_t> encryptedCredentialKeys_;
 
+    // Set by ensureHwProxy()
+    sp<SecureHardwarePresentationProxy> hwProxy_;
+
     // Set by createEphemeralKeyPair()
     vector<uint8_t> ephemeralPublicKey_;