{Public,Private}Key::from_ed25519 should not set keyid_hash_algorithms

python-tuf is [considering] getting rid of keyid_hash_algorithms, so we
shouldn't default to generating keys with them specified.

[considering]: theupdateframework/python-tuf#848

Change-Id: I2c3af5d5eb7b0cc30793b54e45155320164cf706

src/crypto.rs

@@ -370,10 +370,7 @@ impl PrivateKey {
     /// Create a new `PrivateKey` from an ed25519 keypair, a 64 byte slice, where the first 32
     /// bytes are the ed25519 seed, and the second 32 bytes are the public key.
     pub fn from_ed25519(key: &[u8]) -> Result<Self> {
-        Self::from_ed25519_with_keyid_hash_algorithms(
-            key,
-            python_tuf_compatibility_keyid_hash_algorithms(),
-        )
+        Self::from_ed25519_with_keyid_hash_algorithms(key, None)
     }
 
     fn from_ed25519_with_keyid_hash_algorithms(
@@ -661,10 +658,7 @@ impl PublicKey {
 
     /// Parse ED25519 bytes as a public key.
     pub fn from_ed25519<T: Into<Vec<u8>>>(bytes: T) -> Result<Self> {
-        Self::from_ed25519_with_keyid_hash_algorithms(
-            bytes,
-            python_tuf_compatibility_keyid_hash_algorithms(),
-        )
+        Self::from_ed25519_with_keyid_hash_algorithms(bytes, None)
     }
 
     /// Parse ED25519 bytes as a public key with a custom `keyid_hash_algorithms`.
@@ -1026,7 +1020,7 @@ mod test {
         let key = PublicKey::from_ed25519(ED25519_1_PUBLIC_KEY).unwrap();
         assert_eq!(
             key.key_id(),
-            &KeyId::from_str("a9f3ebc9b138762563a9c27b6edd439959e559709babd123e8d449ba2c18c61a")
+            &KeyId::from_str("e0294a3f17cc8563c3ed5fceb3bd8d3f6bfeeaca499b5c9572729ae015566554")
                 .unwrap()
         );
         assert_eq!(key.typ, KeyType::Ed25519);