contracts-bedrock: cleanup

packages/contracts-bedrock/semver-lock.json

 {
   "src/L1/L1CrossDomainMessenger.sol": "0x2b276f14475869cfd81868b03dc72b91dd726a787c9568caf4849fe34830b207",
-  "src/L1/L1ERC721Bridge.sol": "0xc9b9c88b7f46d928443c219d6c99955c6f6bc79f8cf7440d97433f13772dc441",
+  "src/L1/L1ERC721Bridge.sol": "0x6aeb386bab56e1fa45692188ffc0dcb09c6719e17776e1fffd13278f7a5f40cc",
   "src/L1/L1StandardBridge.sol": "0xa35dc0ab143043063c3bff73c8b065e401c23296a2017258ce8a87f4a4da9416",
   "src/L1/L2OutputOracle.sol": "0x8f32ccb4c5cb63a459a0e79ee412177dc03fd279fdaaf1dac69e8c714902e857",
   "src/L1/OptimismPortal.sol": "0xeaa47a63e8a3bcfdb7dfd3e6c8608369e34e362d9de82f3acf13cbc27c070bf7",
@@ -10,7 +10,7 @@
   "src/L2/L1Block.sol": "0x7fbfc8b4da630386636c665570321fdec287b0867dbe0f91c2e7cd5b7697c220",
   "src/L2/L1FeeVault.sol": "0x62bfe739ff939fc68f90916399ac4160936d31eb37749cb014dd9d0c5dd4183a",
   "src/L2/L2CrossDomainMessenger.sol": "0xc9641981f7aa79f44b5925100027098d8f76c6178c65aca99fafa859289182be",
-  "src/L2/L2ERC721Bridge.sol": "0xfedd00d6bbbfe12150b6fbe31047eede706c563fa0b25f2b145c16cb1655dd8a",
+  "src/L2/L2ERC721Bridge.sol": "0x8c43c5f631a79df9f736c6e336af285065e798151e97f11b52bb7d722759f35f",
   "src/L2/L2StandardBridge.sol": "0x67e202bc6751807b20a98b88b0b65bdff30420bf1e71f2c1c7948de448cfcdc0",
   "src/L2/L2ToL1MessagePasser.sol": "0xed800b600cb3f67e18a1ab10750e3934a8b3e42178f422bcacfde770a6e8e8bd",
   "src/L2/SequencerFeeVault.sol": "0xd57c143b1f042400430b991b806bf971628e6980406c751e82d19ae80eeb4e8d",

packages/contracts-bedrock/src/L1/L1ERC721Bridge.sol

@@ -31,7 +31,9 @@ contract L1ERC721Bridge is ERC721Bridge, Semver {
     /// @notice Initializes the contract.
     /// @param _messenger   Address of the CrossDomainMessenger on this network.
     function initialize(CrossDomainMessenger _messenger) public reinitializer(1) {
-        __ERC721Bridge_init(_messenger);
+        __ERC721Bridge_init({
+            _messenger: _messenger
+        });
     }
 
     /// @notice Completes an ERC721 bridge from the other domain and sends the ERC721 token to the
@@ -100,7 +102,7 @@ contract L1ERC721Bridge is ERC721Bridge, Semver {
         IERC721(_localToken).transferFrom(_from, address(this), _tokenId);
 
         // Send calldata into L2
-        _MESSENGER.sendMessage(_OTHER_BRIDGE, message, _minGasLimit);
+        messenger.sendMessage(OTHER_BRIDGE, message, _minGasLimit);
         emit ERC721BridgeInitiated(_localToken, _remoteToken, _from, _to, _tokenId, _extraData);
     }
 }

packages/contracts-bedrock/src/L2/L2ERC721Bridge.sol

@@ -18,11 +18,11 @@ import { Semver } from "../universal/Semver.sol";
 ///         wait for the one-week challenge period to elapse before their Optimism-native NFT
 ///         can be refunded on L2.
 contract L2ERC721Bridge is ERC721Bridge, Semver {
-    /// @custom:semver 1.2.0
+    /// @custom:semver 1.3.0
     /// @notice Constructs the L2ERC721Bridge contract.
     /// @param _otherBridge Address of the ERC721 bridge on the other network.
     constructor(address _otherBridge)
-        Semver(1, 2, 1)
+        Semver(1, 3, 0)
         ERC721Bridge(_otherBridge)
     {
         initialize({
@@ -32,8 +32,10 @@ contract L2ERC721Bridge is ERC721Bridge, Semver {
 
     /// @notice Initializes the contract.
     /// @param _messenger   Address of the CrossDomainMessenger on this network.
-    function initialize(CrossDomainMessenger _messenger) public reinitializer(1) {
-        __ERC721Bridge_init(_messenger);
+    function initialize(CrossDomainMessenger _messenger) public reinitializer(2) {
+        __ERC721Bridge_init({
+            _messenger: _messenger
+        });
     }
 
     /// @notice Completes an ERC721 bridge from the other domain and sends the ERC721 token to the
@@ -119,7 +121,7 @@ contract L2ERC721Bridge is ERC721Bridge, Semver {
 
         // Send message to L1 bridge
         // slither-disable-next-line reentrancy-events
-        _MESSENGER.sendMessage(_OTHER_BRIDGE, message, _minGasLimit);
+        messenger.sendMessage(OTHER_BRIDGE, message, _minGasLimit);
 
         // slither-disable-next-line reentrancy-events
         emit ERC721BridgeInitiated(_localToken, remoteToken, _from, _to, _tokenId, _extraData);

packages/contracts-bedrock/src/universal/ERC721Bridge.sol

@@ -10,10 +10,11 @@ import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable
 abstract contract ERC721Bridge is Initializable {
     /// @notice Messenger contract on this domain.
     /// @custom:network-specific
-    CrossDomainMessenger internal _MESSENGER;
+    CrossDomainMessenger public messenger;
 
     /// @notice Address of the bridge on the other network.
-    address internal immutable _OTHER_BRIDGE;
+    /// @custom:legacy
+    address public immutable OTHER_BRIDGE;
 
     /// @notice Reserve extra slots (to a total of 50) in the storage layout for future upgrades.
     uint256[48] private __gap;
@@ -53,7 +54,7 @@ abstract contract ERC721Bridge is Initializable {
     /// @notice Ensures that the caller is a cross-chain message from the other bridge.
     modifier onlyOtherBridge() {
         require(
-            msg.sender == address(_MESSENGER) && _MESSENGER.xDomainMessageSender() == _OTHER_BRIDGE,
+            msg.sender == address(messenger) && messenger.xDomainMessageSender() == OTHER_BRIDGE,
             "ERC721Bridge: function can only be called from the other bridge"
         );
         _;
@@ -63,38 +64,24 @@ abstract contract ERC721Bridge is Initializable {
     /// @param _otherBridge Address of the ERC721 bridge on the other network.
     constructor(address _otherBridge) {
         require(_otherBridge != address(0), "ERC721Bridge: other bridge cannot be address(0)");
-        _OTHER_BRIDGE = _otherBridge;
+        OTHER_BRIDGE = _otherBridge;
     }
 
     // @notice Initializes the contract.
     /// @param _messenger   Address of the CrossDomainMessenger on this network.
     function __ERC721Bridge_init(CrossDomainMessenger _messenger) internal onlyInitializing {
-        _MESSENGER = _messenger;
+        messenger = _messenger;
     }
 
-    /// @notice Getter for messenger contract.
-    /// @return Messenger contract on this domain.
-    function messenger() external view returns (CrossDomainMessenger) {
-        return _MESSENGER;
-    }
-
-    /// @custom:legacy
     /// @notice Getter for messenger contract.
     function MESSENGER() external view returns (CrossDomainMessenger) {
-        return _MESSENGER;
+        return messenger;
     }
 
     /// @notice Getter for other bridge address.
     /// @return Address of the bridge on the other network.
     function otherBridge() external view returns (address) {
-        return _OTHER_BRIDGE;
-    }
-
-    /// @custom:legacy
-    /// @notice Getter for other bridge address.
-    /// @return Address of the bridge on the other network.
-    function OTHER_BRIDGE() external view returns (address) {
-        return _OTHER_BRIDGE;
+        return OTHER_BRIDGE;
     }
 
     /// @notice Initiates a bridge of an NFT to the caller's account on the other chain. Note that