add internal _setContractMode

contracts/access/manager/AccessManager.sol

@@ -221,26 +221,23 @@ contract AccessManager is IAccessManager, AccessControlDefaultAdminRules {
      * will follow the group-based restrictions defined by the AccessManager. The caller must be the default admin.
      */
     function setContractModeCustom(address target) public virtual onlyDefaultAdmin {
-        _contractMode[target] = RestrictedMode.Custom;
-        emit RestrictedModeUpdated(target, RestrictedMode.Custom);
+        _setContractMode(target, RestrictedMode.Custom);
     }
 
     /**
      * @dev Sets the target contract to be in "open" mode. All restricted functions in the target contract will become
      * callable by anyone. The caller must be the default admin.
      */
     function setContractModeOpen(address target) public virtual onlyDefaultAdmin {
-        _contractMode[target] = RestrictedMode.Open;
-        emit RestrictedModeUpdated(target, RestrictedMode.Open);
+        _setContractMode(target, RestrictedMode.Open);
     }
 
     /**
      * @dev Sets the target contract to be in "closed" mode. All restricted functions in the target contract will be
      * closed down and disallowed to all. The caller must be the default admin.
      */
     function setContractModeClosed(address target) public virtual onlyDefaultAdmin {
-        _contractMode[target] = RestrictedMode.Closed;
-        emit RestrictedModeUpdated(target, RestrictedMode.Closed);
+        _setContractMode(target, RestrictedMode.Closed);
     }
 
     /**
@@ -286,6 +283,14 @@ contract AccessManager is IAccessManager, AccessControlDefaultAdminRules {
         }
     }
 
+    /**
+     * @dev Sets the restricted mode of a target contract.
+     */
+    function _setContractMode(address target, RestrictedMode mode) internal virtual {
+        _contractMode[target] = mode;
+        emit RestrictedModeUpdated(target, mode);
+    }
+
     /**
      * @dev Returns the {AccessControl} role id that corresponds to a group.
      *