static/ext/src/grid/locking/HeaderContainer.js
function () {
        var me = this,
            locked = me.lockable.lockedGrid.headerCt.getColumnsState(),
            normal = me.lockable.normalGrid.headerCt.getColumnsState();

        return locked.concat(normal);
    }
function () {
        var me = this,
            locked = me.lockable.lockedGrid.headerCt.getColumnsState(),
            normal = me.lockable.normalGrid.headerCt.getColumnsState();

        return locked.concat(normal);
    }
Lockable uses its headerCt to gather column state