Adding material to tiled landscape via details pane causes editor to crash

If a material is added to a tiled landscape via the details pane, the editor crashes.

Frequency: 3/3

CrashReporter: [Link Removed]

1. Download attached heightmaps
2. Open editor (any project)
3. In World Settings, enable world composition
4. Open Window>Levels
5. Levels>Import Tiled Landscape>Select Heightmap Tiles (downloaded tiles)>Import
6. Open Placement mode
7. Select landscape tiles
8. Select material (any) in content browser
9. Apply material to landscape via details pane>material

Results:

Editor crashes

Expected:

Material is applied to landscape tiles

MachineId:4E82586D46B558EA69EF0EAA821297B1
EpicAccountId:1558531203f84e81b70959b8a59badef

Unknown exception - code 00000001 (first/second chance not available)

"Assertion failed: !bRenderStateCreated [Link Removed] [Line: 948]
"

KERNELBASE
UE4Editor_Core!FOutputDeviceWindowsError::Serialize() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
UE4Editor_Core!FOutputDevice::Logf__VA() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\misc\outputdevice.cpp:144]
UE4Editor_Core!FDebug::AssertFailed() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\misc\outputdevice.cpp:355]
UE4Editor_Engine!UActorComponent::CreateRenderState_Concurrent() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\engine\private\components\actorcomponent.cpp:953]
UE4Editor_Engine!UPrimitiveComponent::CreateRenderState_Concurrent() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\engine\private\components\primitivecomponent.cpp:285]
UE4Editor_Engine!TIndirectArray<FComponentRecreateRenderStateContext,FDefaultAllocator>::Empty() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\containers\array.h:3193]
UE4Editor_Engine!FGlobalComponentRecreateRenderStateContext::~FGlobalComponentRecreateRenderStateContext() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\engine\private\components\actorcomponent.cpp:96]
UE4Editor_Engine!TScopedPointer<FGlobalComponentRecreateRenderStateContext>::Reset() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\templates\scopedpointer.h:105]
UE4Editor_Engine!FMaterialUpdateContext::~FMaterialUpdateContext() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\engine\private\materials\materialshared.cpp:2093]
UE4Editor_Landscape!ALandscapeProxy::PostEditChangeProperty() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\landscape\private\landscapeedit.cpp:3193]
UE4Editor_CoreUObject!UObject::PostEditChangeChainProperty() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\coreuobject\private\uobject\obj.cpp:376]
UE4Editor_Landscape!ALandscapeProxy::PostEditChangeChainProperty() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\landscape\private\landscapeedit.cpp:3300]
UE4Editor_PropertyEditor!FPropertyNode::NotifyPostChange() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\propertynode.cpp:1979]
UE4Editor_PropertyEditor!FPropertyValueImpl::ImportText() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\propertyhandleimpl.cpp:446]
UE4Editor_PropertyEditor!FPropertyValueImpl::ImportText() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\propertyhandleimpl.cpp:297]
UE4Editor_PropertyEditor!FPropertyValueImpl::SendTextToObjectProperty() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\propertyhandleimpl.cpp:253]
UE4Editor_PropertyEditor!FPropertyHandleObject::SetValue() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\propertyhandleimpl.cpp:2373]
UE4Editor_PropertyEditor!SPropertyEditorAsset::SetValue() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\userinterface\propertyeditor\spropertyeditorasset.cpp:521]
UE4Editor_PropertyEditor!SPropertyEditorAsset::OnAssetDropped() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\propertyeditor\private\userinterface\propertyeditor\spropertyeditorasset.cpp:777]
UE4Editor_PropertyEditor!TBaseSPMethodDelegateInstance<0,SPropertyEditorAsset,0,TTypeWrapper<void> __cdecl(UObject * __ptr64)>::Execute() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:282]
UE4Editor_PropertyEditor!TBaseSPMethodDelegateInstance<0,SPropertyEditorAsset,0,void __cdecl(UObject * __ptr64)>::ExecuteIfSafe() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:388]
UE4Editor_EditorWidgets!SAssetDropTarget::OnDropped() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\editorwidgets\private\sassetdroptarget.cpp:35]
UE4Editor_EditorWidgets!TMemberFunctionCaller<SAssetDropTarget,FReply (__cdecl SAssetDropTarget::*)(TSharedPtr<FDragDropOperation,0>) __ptr64>::operator()<TSharedPtr<FDragDropOperation,0> & __ptr64>() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\delegateinstanceinterface_variadics.h:161]
UE4Editor_EditorWidgets!TTupleImpl<TIntegerSequence<> >::ApplyAfter_ExplicitReturnType<FReply,TMemberFunctionCaller<SAssetDropTarget,FReply (__cdecl SAssetDropTarget::*)(TSharedPtr<FDragDropOperation,0>) __ptr64>,TSharedPtr<FDragDropOperation,0> & __ptr64>() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\tuple.h:113]
UE4Editor_EditorWidgets!TBaseSPMethodDelegateInstance<0,SAssetDropTarget,0,FReply __cdecl(TSharedPtr<FDragDropOperation,0>)>::Execute() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:282]
UE4Editor_EditorWidgets!TBaseDelegate<FReply,TSharedPtr<FDragDropOperation,0> >::Execute() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\public\delegates\delegatesignatureimpl_variadics.inl:440]
UE4Editor_EditorWidgets!SDropTarget::OnDrop() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\editor\editorwidgets\private\sdroptarget.cpp:124]
UE4Editor_Slate!<lambda_13af6b42409306e44b4e7065f2966a1b>::operator()() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4210]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FPointerEvent,<lambda_13af6b42409306e44b4e7065f2966a1b> >() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:212]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4213]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4133]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsapplication.cpp:1406]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsapplication.cpp:1711]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsapplication.cpp:706]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsapplication.cpp:628]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:792]
UE4Editor!FEngineLoop::Tick() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\launchengineloop.cpp:2319]
UE4Editor!GuardedMain() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\launch.cpp:142]
UE4Editor!GuardedMainWrapper() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\buildfarm\buildmachine_++depot+ue4-releases+4.8\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]

UE4.8 crash using material with level composition