Don't raise events in separated threads

[ALiwoto]

Using Task.Run is not acceptable everywhere

	[EditorBrowsable(EditorBrowsableState.Never)]
	protected internal virtual void OnRightUp()
	{
		Task.Run((() =>
		{
			// raise the event in another thread.
			this.RightUp?.Invoke(this, null);
		}));
	}

So what's wrong with this code?

1. You are creating a new thread, even if the action won't do anything.
2. You are running every single event on a whole separated thread.

This will cause some problems in the future, such as hug memory leak.

---

So what to do?

I think something like this will be okay:

	[EditorBrowsable(EditorBrowsableState.Never)]
	protected internal virtual void OnRightUp()
	{
		this.RightUp?.Invoke(this, null);
		if (this.RightUpAsync != null)
		{
			Task.Run((() =>
			{
				// raise the event in another thread.
				this.RightUpAsync?.Invoke(this, null);
			}));
		}
	}

This way, we won't create new threads over and over.