Store password in vold

If we are not to double prompt, we need to pass the password from
CryptKeeper to KeyStore. Since the entire framework is taken down
and restarted, we must store the password in a secure system daemon.
There seems no better way than holding it in vold.

Change-Id: Ia60f2f051fc3f87c4b6468465f17b655f43f97de
diff --git a/cryptfs.h b/cryptfs.h
index ac678dc..c26f127 100644
--- a/cryptfs.h
+++ b/cryptfs.h
@@ -166,7 +166,8 @@
   int cryptfs_setfield(char *fieldname, char *value);
   int cryptfs_mount_default_encrypted(void);
   int cryptfs_get_password_type(void);
-  int cryptfs_just_decrypted(void);
+  char* cryptfs_get_password(void);
+  void cryptfs_clear_password(void);
 #ifdef __cplusplus
 }
 #endif