Visibility Notifier / Enabler classref mention Portals

Fixes the classref to show that these do not take account of occlusion except when using Portals.

(cherry picked from commit b8d3d97b6ab7dd31872dc357bd6abca33399e22d)

doc/classes/VisibilityEnabler.xml

@@ -6,7 +6,7 @@
 	<description>
 		The VisibilityEnabler will disable [RigidBody] and [AnimationPlayer] nodes when they are not visible. It will only affect other nodes within the same scene as the VisibilityEnabler itself.
 		If you just want to receive notifications, use [VisibilityNotifier] instead.
-		[b]Note:[/b] VisibilityEnabler uses an approximate heuristic for performance reasons. It doesn't take walls and other occlusion into account. The heuristic is an implementation detail and may change in future versions. If you need precise visibility checking, use another method such as adding an [Area] node as a child of a [Camera] node and/or [method Vector3.dot].
+		[b]Note:[/b] VisibilityEnabler uses an approximate heuristic for performance reasons. It doesn't take walls and other occlusion into account (unless you are using [Portal]s). The heuristic is an implementation detail and may change in future versions. If you need precise visibility checking, use another method such as adding an [Area] node as a child of a [Camera] node and/or [method Vector3.dot].
 		[b]Note:[/b] VisibilityEnabler will not affect nodes added after scene initialization.
 	</description>
 	<tutorials>

doc/classes/VisibilityNotifier.xml

@@ -6,7 +6,7 @@
 	<description>
 		The VisibilityNotifier detects when it is visible on the screen. It also notifies when its bounding rectangle enters or exits the screen or a [Camera]'s view.
 		If you want nodes to be disabled automatically when they exit the screen, use [VisibilityEnabler] instead.
-		[b]Note:[/b] VisibilityNotifier uses an approximate heuristic for performance reasons. It doesn't take walls and other occlusion into account. The heuristic is an implementation detail and may change in future versions. If you need precise visibility checking, use another method such as adding an [Area] node as a child of a [Camera] node and/or [method Vector3.dot].
+		[b]Note:[/b] VisibilityNotifier uses an approximate heuristic for performance reasons. It doesn't take walls and other occlusion into account (unless you are using [Portal]s). The heuristic is an implementation detail and may change in future versions. If you need precise visibility checking, use another method such as adding an [Area] node as a child of a [Camera] node and/or [method Vector3.dot].
 	</description>
 	<tutorials>
 	</tutorials>