Editor - Fix ObjectPropertyEntryBox to once again work without a PropertyHandle
Backed out part of changelist 2320455 to get the Asset Override Editor selection boxes working again.
#codereview Richard.TalbotWatkin
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Integrated using branch Ue4-To-UE4-Fortnite-Simple (reversed) of change#2325726 by Jaren.Peterson on 2014/10/10 13:29:25.
[CL 2325858 by Jaren Peterson in Main branch]
#ttp 339373 - Crash: when you create a endless loop with material instance that has it self as a parent the editor will become unresponsive
#branch UE4
#proj Editor.MaterialEditor, Editor.UnrealEd, Runtime.Engine
[CL 2320455 by Richard TalbotWatkin in Main branch]
#ttp 345817 - NUX: MVP: Asset pickers should have Create New button
#branch UE4
#proj Editor.PropertyEditor, Editor.DetailCustomizations
[CL 2320429 by Richard TalbotWatkin in Main branch]
TTP# 279062 - ROCKET: TASK: PUNTABLE: Viewports: "Drag to Attach" feature
Moved FEdModePicker out of the Private section of the PropertyEditor module, and into its own module so that it can be shared between the PropertyEditor and LevelEditor modules. Also renamed it to FEdModeActorPicker.
Added a way to filter FEdModeActorPicker by checking the actor directly (this complements the class type check it already had).
Added an actor picker button next to the scene outliner in the "Attach To" menu on actors. This is also mapped to the Alt+A command.
Built and tested in unity and non-unity.
ReviewedBy Thomas.Sarkanen, Max.Preussner
[CL 2060928 by Jamie Dale in Main branch]
This allows the filtering of any actors that are part of the specified folder.
This addresses TTP#331604 - EDITOR: Scene Outliner: Folders will appear in the drop down when you try to move them, and TTP#331640 - EDITOR: Scene Outliner: In the 'Move to Folder" sub menu the "Create New" tooltip is incorrect
Also fixed not being able to move attached actors to a folder
Reviewed by Matt Kuhlenschmidt
[CL 2058587 by Andrew Rodham in Main branch]
