function removeGlobalKeydownHook(hook) {
        var index = _globalKeydownHooks.indexOf(hook);
        if (index !== -1) {
            _globalKeydownHooks.splice(index, 1);
        }
    }
function removeGlobalKeydownHook(hook) {
        var index = _globalKeydownHooks.indexOf(hook);
        if (index !== -1) {
            _globalKeydownHooks.splice(index, 1);
        }
    }
function removeGlobalKeydownHook ( hook ) { var index = _globalKeydownHooks . indexOf ( hook ) ; if ( index !== - 1 ) { _globalKeydownHooks . splice ( index , 1 ) ; } }
Removes a global keydown hook added by `addGlobalKeydownHook`.
Does not need to be the most recently added hook.

@param {function(Event): boolean} hook The global hook to remove.
Removes a global keydown hook added by addGlobalKeydownHook . Does not need to be the most recently added hook .
Remove a global keydown hook