Non-terrain-gem changes in support of upcoming terrain work. (#3345)

In preparation for a prototype Terrain Gem to get submitted, there are a few changes that are needed outside of the Terrain Gem as well:

The TerrainDataNotificationBus lives in AzFramework/Terrain, and needed to be extended to contain an optional OnTerrainDataChanged event to notify other systems when a terrain region has changed.
The HeightmapUpdateNotificationBus was removed, as this was a legacy file from the old already-removed terrain system.
The EditorWrappedComponentBase<> wrapper received a small optimization to ensure that ConfigurationChanged() is only called when the value of visibility actually changes. With prefabs, it appears that sometimes OnEntityVisibilityChanged could be called multiple times in a row with the same visibility value.
The TerrainSurfaceDataSystemComponent was updated to use the correct busses, and is ready to be moved to the Terrain Gem in a subsequent PR.

Signed-off-by: Mike Balfour 82224783+mbalfour-amzn@users.noreply.github.com

Code/Legacy/CryCommon/HeightmapUpdateNotificationBus.h

@@ -1,34 +0,0 @@
-/*
- * Copyright (c) Contributors to the Open 3D Engine Project.
- * For complete copyright and license terms please see the LICENSE at the root of this distribution.
- *
- * SPDX-License-Identifier: Apache-2.0 OR MIT
- *
- */
-
-#pragma once
-
-#include <AzCore/EBus/EBus.h>
-#include <AzCore/Math/Aabb.h>
-
-namespace AZ
-{
-    /**
-    * the EBus is used to request information about potential vegetation surfaces
-    */
-    class HeightmapUpdateNotification
-        : public AZ::EBusTraits
-    {
-    public:
-        ////////////////////////////////////////////////////////////////////////
-        // EBusTraits
-        static const AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Multiple;
-        static const AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::Single;
-        ////////////////////////////////////////////////////////////////////////
-
-        // Occurs when the terrain height map is modified.
-        virtual void HeightmapModified(const AZ::Aabb& bounds) = 0;
-    };
-
-    typedef AZ::EBus<HeightmapUpdateNotification> HeightmapUpdateNotificationBus;
-}

Code/Legacy/CryCommon/crycommon_files.cmake

@@ -53,7 +53,6 @@ set(FILES
     HMDBus.h
     VRCommon.h
     StereoRendererBus.h
-    HeightmapUpdateNotificationBus.h
     INavigationSystem.h
     IMNM.h
     SFunctor.h