VR Mode - Landscape Mode - Flatten tool crash

Crash will occur when attempting to use Flatten tool on landscape while in VR Editor.

Confirmed in 4.24 MAIN @ CL 9084132

Confirmed on Vive and Rift

1. Create a Landscape 
2. Select Flatten tool.  (You must select flatten tool before entering VR Mode [Link Removed] )
3. Enter VR Mode -> VR Landscape Editing
4. Attempt to Flatten terrain

Result: Crash

Unhandled exception

UE4Editor_LandscapeEditor!FLandscapeToolFlatten<FHeightmapToolTarget>::MouseMove() [d:\build\++ue4\sync\engine\source\editor\landscapeeditor\private\landscapeedmodepainttools.cpp:1073]
UE4Editor_LandscapeEditor!FEdModeLandscape::OnVRHoverUpdate() [d:\build\++ue4\sync\engine\source\editor\landscapeeditor\private\landscapeedmode.cpp:901]
UE4Editor_LandscapeEditor!TBaseRawMethodDelegateInstance<0,FEdModeLandscape,void __cdecl(UViewportInteractor *,FVector &,bool &)>::ExecuteIfSafe() [d:\build\++ue4\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:541]
UE4Editor_ViewportInteraction!UViewportWorldInteraction::HoverTick() [d:\build\++ue4\sync\engine\source\editor\viewportinteraction\viewportworldinteraction.cpp:840]
UE4Editor_ViewportInteraction!UViewportWorldInteraction::Tick() [d:\build\++ue4\sync\engine\source\editor\viewportinteraction\viewportworldinteraction.cpp:484]
UE4Editor_UnrealEd!UEditorWorldExtensionManager::Tick() [d:\build\++ue4\sync\engine\source\editor\unrealed\private\editorworldextension.cpp:646]
UE4Editor_UnrealEd!UEditorEngine::Tick() [d:\build\++ue4\sync\engine\source\editor\unrealed\private\editorengine.cpp:1702]
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [d:\build\++ue4\sync\engine\source\editor\unrealed\private\unrealedengine.cpp:407]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4\sync\engine\source\runtime\launch\private\launchengineloop.cpp:4257]
UE4Editor!GuardedMain() [d:\build\++ue4\sync\engine\source\runtime\launch\private\launch.cpp:173]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:147]
UE4Editor!WinMain() [d:\build\++ue4\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:279]
UE4Editor!__scrt_common_main_seh() [d:\agent\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll