Keystore 2.0: Make VPN Keystore 2.0 ready.

* Use public stable API to load certificates from keystore.
* Also use grants to allow racoon to use keystore keys without
  special exceptions in keystore.
* Use LegacyProfileStore instead of Keystore for storing VPN profiles.

Bug: 175068876
Bug: 171305607
Test: atest android.net.cts.Ikev2VpnTest
      atest android.net.cts.IpSecManagerTest
      atest com.android.server.connectivity.VpnTest
      atest com.android.server.ConnectivityServiceTest
Merged-In: I27975113896ea137260a9f94a34fb1c3ca173fe3
Change-Id: I27975113896ea137260a9f94a34fb1c3ca173fe3
diff --git a/Android.bp b/Android.bp
index 0d7deb1..e79248e 100644
--- a/Android.bp
+++ b/Android.bp
@@ -526,6 +526,7 @@
         "android.security.apc-java",
         "android.security.authorization-java",
         "android.security.usermanager-java",
+        "android.security.vpnprofilestore-java",
         "android.system.keystore2-V1-java",
         "android.system.suspend.control.internal-java",
         "devicepolicyprotosnano",