Keystore 2.0: Implement legacy blob support.

This CL implements on-demand migration of legacy key blobs into
the Keystore 2.0.

This CL has joined authorship by
hasinigt@google.com and jdanis@google.com

Test: keystore2_test
      CTS Test.
      And manual test with key upgrade app.
Change-Id: I0a1f266c12f06cc2e196692d759dedf48b4d347a
diff --git a/keystore2/src/lib.rs b/keystore2/src/lib.rs
index 445aef6..358fce8 100644
--- a/keystore2/src/lib.rs
+++ b/keystore2/src/lib.rs
@@ -24,6 +24,7 @@
 /// Internal Representation of Key Parameter and convenience functions.
 pub mod key_parameter;
 pub mod legacy_blob;
+pub mod legacy_migrator;
 pub mod operation;
 pub mod permission;
 pub mod remote_provisioning;