contracts-bedrock: remove crossdomain messenger pausability

packages/contracts-bedrock/.storage-layout

@@ -11,11 +11,11 @@
 | spacer_0_0_20          | address                  | 0    | 0      | 20    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 | _initialized           | uint8                    | 0    | 20     | 1     | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 | _initializing          | bool                     | 0    | 21     | 1     | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-| __gap                  | uint256[50]              | 1    | 0      | 1600  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-| _owner                 | address                  | 51   | 0      | 20    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-| __gap                  | uint256[49]              | 52   | 0      | 1568  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-| _paused                | bool                     | 101  | 0      | 1     | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
-| __gap                  | uint256[49]              | 102  | 0      | 1568  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
+| spacer_1_0_1600        | uint256[50]              | 1    | 0      | 1600  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
+| spacer_51_0_20         | address                  | 51   | 0      | 20    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
+| spacer_52_0_1568       | uint256[49]              | 52   | 0      | 1568  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
+| spacer_101_0_1         | bool                     | 101  | 0      | 1     | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
+| spacer_102_0_1568      | uint256[49]              | 102  | 0      | 1568  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 | spacer_151_0_32        | uint256                  | 151  | 0      | 32    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 | __gap_reentrancy_guard | uint256[49]              | 152  | 0      | 1568  | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
 | spacer_201_0_32        | mapping(bytes32 => bool) | 201  | 0      | 32    | contracts/L1/L1CrossDomainMessenger.sol:L1CrossDomainMessenger |
@@ -121,11 +121,11 @@
 | spacer_0_0_20          | address                  | 0    | 0      | 20    | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
 | _initialized           | uint8                    | 0    | 20     | 1     | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
 | _initializing          | bool                     | 0    | 21     | 1     | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
-| __gap                  | uint256[50]              | 1    | 0      | 1600  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
-| _owner                 | address                  | 51   | 0      | 20    | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
-| __gap                  | uint256[49]              | 52   | 0      | 1568  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
-| _paused                | bool                     | 101  | 0      | 1     | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
-| __gap                  | uint256[49]              | 102  | 0      | 1568  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
+| spacer_1_0_1600        | uint256[50]              | 1    | 0      | 1600  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
+| spacer_51_0_20         | address                  | 51   | 0      | 20    | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
+| spacer_52_0_1568       | uint256[49]              | 52   | 0      | 1568  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
+| spacer_101_0_1         | bool                     | 101  | 0      | 1     | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
+| spacer_102_0_1568      | uint256[49]              | 102  | 0      | 1568  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
 | spacer_151_0_32        | uint256                  | 151  | 0      | 32    | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
 | __gap_reentrancy_guard | uint256[49]              | 152  | 0      | 1568  | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |
 | spacer_201_0_32        | mapping(bytes32 => bool) | 201  | 0      | 32    | contracts/L2/L2CrossDomainMessenger.sol:L2CrossDomainMessenger |

packages/contracts-bedrock/contracts/L1/L1CrossDomainMessenger.sol

@@ -29,17 +29,14 @@ contract L1CrossDomainMessenger is CrossDomainMessenger, Semver {
         CrossDomainMessenger(Predeploys.L2_CROSS_DOMAIN_MESSENGER)
     {
         PORTAL = _portal;
-        initialize(address(0));
+        initialize();
     }
 
     /**
      * @notice Initializer.
-     *
-     * @param _owner Address of the initial owner of this contract.
      */
-    function initialize(address _owner) public initializer {
+    function initialize() public initializer {
         __CrossDomainMessenger_init();
-        _transferOwnership(_owner);
     }
 
     /**

packages/contracts-bedrock/contracts/deployment/SystemDictator.sol

@@ -335,7 +335,7 @@ contract SystemDictator is OwnableUpgradeable {
         // Try to initialize the L1CrossDomainMessenger, only fail if it's already been initialized.
         try
             L1CrossDomainMessenger(config.proxyAddressConfig.l1CrossDomainMessengerProxy)
-                .initialize(address(this))
+                .initialize()
         {
             // L1CrossDomainMessenger is the one annoying edge case difference between existing
             // networks and fresh networks because in existing networks it'll already be
@@ -375,27 +375,12 @@ contract SystemDictator is OwnableUpgradeable {
             payable(config.proxyAddressConfig.l1ERC721BridgeProxy),
             address(config.implementationAddressConfig.l1ERC721BridgeImpl)
         );
-
-        // Pause the L1CrossDomainMessenger, chance to check that everything is OK.
-        L1CrossDomainMessenger(config.proxyAddressConfig.l1CrossDomainMessengerProxy).pause();
-    }
-
-    /**
-     * @notice Unpauses the system at which point the system should be fully operational.
-     */
-    function step6() external onlyOwner step(6) {
-        // Unpause the L1CrossDomainMessenger.
-        L1CrossDomainMessenger(config.proxyAddressConfig.l1CrossDomainMessengerProxy).unpause();
     }
 
     /**
      * @notice Tranfers admin ownership to the final owner.
      */
     function finalize() external onlyOwner {
-        // Transfer ownership of the L1CrossDomainMessenger to the final owner.
-        L1CrossDomainMessenger(config.proxyAddressConfig.l1CrossDomainMessengerProxy)
-            .transferOwnership(config.globalConfig.finalOwner);
-
         // Transfer ownership of the ProxyAdmin to the final owner.
         config.globalConfig.proxyAdmin.transferOwnership(config.globalConfig.finalOwner);
 

packages/contracts-bedrock/contracts/test/CommonTest.t.sol

@@ -254,7 +254,7 @@ contract Messenger_Initializer is L2OutputOracle_Initializer {
             "OVM_L1CrossDomainMessenger"
         );
         L1Messenger = L1CrossDomainMessenger(address(proxy));
-        L1Messenger.initialize(alice);
+        L1Messenger.initialize();
 
         vm.etch(
             Predeploys.L2_CROSS_DOMAIN_MESSENGER,

packages/contracts-bedrock/contracts/test/L1CrossDomainMessenger.t.sol

@@ -25,42 +25,6 @@ contract L1CrossDomainMessenger_Test is Messenger_Initializer {
     // Storage slot of the l2Sender
     uint256 constant senderSlotIndex = 50;
 
-    function setUp() public override {
-        super.setUp();
-    }
-
-    // pause: should pause the contract when called by the current owner
-    function test_pause_succeeds() external {
-        vm.prank(alice);
-        L1Messenger.pause();
-        assert(L1Messenger.paused());
-    }
-
-    // pause: should not pause the contract when called by account other than the owner
-    function test_pause_callerIsNotOwner_reverts() external {
-        vm.expectRevert("Ownable: caller is not the owner");
-        vm.prank(address(0xABBA));
-        L1Messenger.pause();
-    }
-
-    // unpause: should unpause the contract when called by the current owner
-    function test_unpause_succeeds() external {
-        vm.prank(alice);
-        L1Messenger.pause();
-        assert(L1Messenger.paused());
-
-        vm.prank(alice);
-        L1Messenger.unpause();
-        assert(!L1Messenger.paused());
-    }
-
-    // unpause: should not unpause the contract when called by account other than the owner
-    function test_unpause_callerIsNotOwner_reverts() external {
-        vm.expectRevert("Ownable: caller is not the owner");
-        vm.prank(address(0xABBA));
-        L1Messenger.unpause();
-    }
-
     // the version is encoded in the nonce
     function test_messageVersion_succeeds() external {
         (, uint16 version) = Encoding.decodeVersionedNonce(L1Messenger.messageNonce());
@@ -274,15 +238,6 @@ contract L1CrossDomainMessenger_Test is Messenger_Initializer {
         L1Messenger.xDomainMessageSender();
     }
 
-    // relayMessage: should revert if paused
-    function test_relayMessage_paused_reverts() external {
-        vm.prank(L1Messenger.owner());
-        L1Messenger.pause();
-
-        vm.expectRevert("Pausable: paused");
-        L1Messenger.relayMessage(0, address(0), address(0), 0, 0, hex"");
-    }
-
     // relayMessage: should send a successful call to the target contract after the first message
     // fails and ETH gets stuck, but the second message succeeds
     function test_relayMessage_retryAfterFailure_succeeds() external {

packages/contracts-bedrock/contracts/test/L2CrossDomainMessenger.t.sol

@@ -16,21 +16,6 @@ contract L2CrossDomainMessenger_Test is Messenger_Initializer {
     // Receiver address for testing
     address recipient = address(0xabbaacdc);
 
-    function setUp() public override {
-        super.setUp();
-    }
-
-    function test_pause_succeeds() external {
-        L2Messenger.pause();
-        assert(L2Messenger.paused());
-    }
-
-    function test_pause_notOwner_reverts() external {
-        vm.expectRevert("Ownable: caller is not the owner");
-        vm.prank(address(0xABBA));
-        L2Messenger.pause();
-    }
-
     function test_messageVersion_succeeds() external {
         (, uint16 version) = Encoding.decodeVersionedNonce(L2Messenger.messageNonce());
         assertEq(version, L2Messenger.MESSAGE_VERSION());
@@ -191,15 +176,6 @@ contract L2CrossDomainMessenger_Test is Messenger_Initializer {
         L2Messenger.xDomainMessageSender();
     }
 
-    // relayMessage: should revert if paused
-    function test_relayMessage_paused_reverts() external {
-        vm.prank(L2Messenger.owner());
-        L2Messenger.pause();
-
-        vm.expectRevert("Pausable: paused");
-        L2Messenger.relayMessage(0, address(0), address(0), 0, 0, hex"");
-    }
-
     // relayMessage: should send a successful call to the target contract after the first message
     // fails and ETH gets stuck, but the second message succeeds
     function test_relayMessage_retry_succeeds() external {

packages/contracts-bedrock/contracts/universal/CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.15;
 
-import {
-    OwnableUpgradeable
-} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
-import {
-    PausableUpgradeable
-} from "@openzeppelin/contracts-upgradeable/security/PausableUpgradeable.sol";
+import { Initializable } from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
 import { SafeCall } from "../libraries/SafeCall.sol";
 import { Hashing } from "../libraries/Hashing.sol";
 import { Encoding } from "../libraries/Encoding.sol";
@@ -14,12 +9,12 @@ import { Constants } from "../libraries/Constants.sol";
 
 /**
  * @custom:legacy
- * @title CrossDomainMessengerLegacySpacer
+ * @title CrossDomainMessengerLegacySpacer0
  * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
  *         libAddressManager variable used to exist. Must be the first contract in the inheritance
- *         tree of the CrossDomainMessenger
+ *         tree of the CrossDomainMessenger.
  */
-contract CrossDomainMessengerLegacySpacer {
+contract CrossDomainMessengerLegacySpacer0 {
     /**
      * @custom:legacy
      * @custom:spacer libAddressManager
@@ -28,6 +23,50 @@ contract CrossDomainMessengerLegacySpacer {
     address private spacer_0_0_20;
 }
 
+/**
+ * @custom:legacy
+ * @title CrossDomainMessengerLegacySpacer1
+ * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
+ *         PausableUpgradable and OwnableUpgradeable variables used to exist. Must be
+ *         the third contract in the inheritance tree of the CrossDomainMessenger.
+ */
+contract CrossDomainMessengerLegacySpacer1 {
+    /**
+     * @custom:legacy
+     * @custom:spacer __gap
+     * @notice Spacer for backwards compatibility.
+     */
+    uint256[50] private spacer_1_0_1600;
+
+    /**
+     * @custom:legacy
+     * @custom:spacer _owner
+     * @notice Spacer for backwards compatibility.
+     */
+    address private spacer_51_0_20;
+
+    /**
+     * @custom:legacy
+     * @custom:spacer __gap
+     * @notice Spacer for backwards compatibility.
+     */
+    uint256[49] private spacer_52_0_1568;
+
+    /**
+     * @custom:legacy
+     * @custom:spacer _paused
+     * @notice Spacer for backwards compatibility.
+     */
+    bool private spacer_101_0_1;
+
+    /**
+     * @custom:legacy
+     * @custom:spacer __gap
+     * @notice
+     */
+    uint256[49] private spacer_102_0_1568;
+}
+
 /**
  * @custom:upgradeable
  * @title CrossDomainMessenger
@@ -36,11 +75,13 @@ contract CrossDomainMessengerLegacySpacer {
  *         needs to be extended slightly to provide low-level message passing functionality on each
  *         chain it's deployed on. Currently only designed for message passing between two paired
  *         chains and does not support one-to-many interactions.
+ *
+ *         Any changes to this contract MUST result in a semver bump for contracts that inherit it.
  */
 abstract contract CrossDomainMessenger is
-    CrossDomainMessengerLegacySpacer,
-    OwnableUpgradeable,
-    PausableUpgradeable
+    CrossDomainMessengerLegacySpacer0,
+    Initializable,
+    CrossDomainMessengerLegacySpacer1
 {
     /**
      * @notice Current message version identifier.
@@ -196,22 +237,6 @@ abstract contract CrossDomainMessenger is
         OTHER_MESSENGER = _otherMessenger;
     }
 
-    /**
-     * @notice Allows the owner of this contract to temporarily pause message relaying. Backup
-     *         security mechanism just in case. Owner should be the same as the upgrade wallet to
-     *         maintain the security model of the system as a whole.
-     */
-    function pause() external onlyOwner {
-        _pause();
-    }
-
-    /**
-     * @notice Allows the owner of this contract to resume message relaying once paused.
-     */
-    function unpause() external onlyOwner {
-        _unpause();
-    }
-
     /**
      * @notice Sends a message to some target address on the other chain. Note that if the call
      *         always reverts, then the message will be unrelayable, and any ETH sent will be
@@ -273,7 +298,7 @@ abstract contract CrossDomainMessenger is
         uint256 _value,
         uint256 _minGasLimit,
         bytes calldata _message
-    ) external payable whenNotPaused {
+    ) external payable {
         (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
         require(
             version < 2,
@@ -423,9 +448,6 @@ abstract contract CrossDomainMessenger is
     // solhint-disable-next-line func-name-mixedcase
     function __CrossDomainMessenger_init() internal onlyInitializing {
         xDomainMsgSender = Constants.DEFAULT_L2_SENDER;
-        __Context_init_unchained();
-        __Ownable_init_unchained();
-        __Pausable_init_unchained();
     }
 
     /**

packages/contracts-bedrock/deploy/021-SystemDictatorSteps-2.ts

@@ -204,16 +204,15 @@ const deployFn: DeployFunction = async (hre) => {
     )
   }
 
-  // Step 5 initializes all contracts and pauses the new L1CrossDomainMessenger.
+  // Step 5 initializes all contracts.
   await doStep({
     isLiveDeployer,
     SystemDictator,
     step: 5,
     message: `
-      Step 5 will initialize all Bedrock contracts but will leave the new L1CrossDomainMessenger
-      paused. After this step is executed, users will be able to deposit and withdraw assets via
-      the OptimismPortal but not via the L1CrossDomainMessenger. The Proposer will also be able to
-      submit L2 outputs to the L2OutputOracle.
+      Step 5 will initialize all Bedrock contracts After this step is executed, the OptimismPortal
+      will be open for deposits but withdrawals will be paused if deploying a production network.
+      The Proposer will also be able to submit L2 outputs to the L2OutputOracle.
     `,
     checks: async () => {
       // Check L2OutputOracle was initialized properly.
@@ -253,7 +252,6 @@ const deployFn: DeployFunction = async (hre) => {
       }
 
       // Check L1CrossDomainMessenger was initialized properly.
-      await assertContractVariable(L1CrossDomainMessenger, 'paused', true)
       try {
         await L1CrossDomainMessenger.xDomainMessageSender()
         assert(false, `L1CrossDomainMessenger was not initialized properly`)
@@ -292,6 +290,7 @@ const deployFn: DeployFunction = async (hre) => {
     },
   })
 
+  // Step 6 unpauses the OptimismPortal.
   if (await isStep(SystemDictator, 6)) {
     console.log(`
       Unpause the OptimismPortal. The GUARDIAN account should be used. In practice
@@ -321,21 +320,6 @@ const deployFn: DeployFunction = async (hre) => {
     )
   }
 
-  // Step 6 unpauses the new L1CrossDomainMessenger.
-  await doStep({
-    isLiveDeployer,
-    SystemDictator,
-    step: 6,
-    message: `
-      Step 6 will unpause the new L1CrossDomainMessenger. After this step is executed, users will
-      be able to deposit and withdraw assets via the L1CrossDomainMessenger and the system will be
-      fully operational.
-    `,
-    checks: async () => {
-      await assertContractVariable(L1CrossDomainMessenger, 'paused', false)
-    },
-  })
-
   // At the end we finalize the upgrade.
   if (await isStep(SystemDictator, 7)) {
     console.log(`