The legacy M.core.event.BLOCK_CONTENT_UPDATED event has been replaced with a
new core_block/events::blockContentUpdated native DOM event.
The new event can be triggered using the `notifyBlockContentUpdated`
event, and by providing the HTMLElement that was updated, for example:
```
import {notifyBlockContentUpdated} from 'core_block/events';
const someHandler = e => {
// ...
const updatedBlock = e.target.closest('.block');
notifyBlockContentUpdated(updatedBlock);
};
```
The new event can be listened to at any point in the DOM using the
following syntax:
```
import {eventTypes} from 'core_block/events';
const handler = e => {
// The block that was updated.
e.target;
// The id of the updated block.
e.detail.instanceId;
};
document.addEventListener(eventTypes.blockContentUpdated, handler);
```
A backward-compatabibility layer is included to ensure that any legacy
YUI event listener is still called with the same arguments.
This legacy bridges will be removed after Moodle 4.3.
Also:
* In behat, ensure nav node exists before checking attribute (Credit to
Rajesh Taneja)
* Remove some unused JS constants
* Fix debugging notice for users without settings block
Andrew Nicols