The object reference replacement archives can't serialize linkers which may hold references to the objects in question. Resetting loaders before we run this code ensures there are no unreachable references.
This addresses UE-13884 and UE-13877
Reviewed by Rob Manuszewski
[CL 2540729 by Andrew Rodham in Main branch]
#jira UE-9362 - Deleting an actor blueprint that has instances in a level offers a replace references option that can explode
#reviewedby Chris.Gagnon
[CL 2511580 by Richard TalbotWatkin in Main branch]
#UE4 Fixed some faulty logic in ShowDeleteConfirmationDialog that incorrectly removed all packages from the delete list.
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Integrated using branch Ue4-To-UE4-Fortnite-Simple (reversed) of change#2499176 by Bob.Tellez on 2015/04/01 17:40:29.
[CL 2499177 by Bob Tellez in Main branch]
#jira UE-11175 - CRASH: Simultaneously deleting an in-level blueprint and the blueprint it's been reparented to
[CL 2471614 by Michael Schoell in Main branch]
[UE-9497] Clear the blueprint's generated class's CDO before deleting the blueprint, otherwise it gets redirected to the replacing type and that causes a an assertion
#lockdown Nick.Whiting
[CL 2449925 by Matthew Griffin in Main branch]
Delete Blueprint Class instances when users force delete the source asset.
#jira UE-7247 - Editor locks on PIE after deleting BP with billboard and another component
change summary:
- alert and clear transaction buffer on delete when instances are present
- modified ForceDeleteObjects() to find and destroy BPGC instances (routing through standard editor code paths for Actor-based instances to ensure that references are cleared, panels are updated, etc.)
[CL 2425868 by Ben Marsh in Main branch]
Improved the validation when drag-and-dropping a class into the level viewport
UE-7184 - Show game c++ classes and engine c++ classes in the content browser
It now prevents the placement of non-placeable classes that have come from an asset or class drag (Content Browser or Class Viewer).
[CL 2425767 by Ben Marsh in Main branch]
UETOOL-213 - Minimize Slate FString -> FText conversion (remove SLATE_TEXT_ATTRIBUTE)
This fixes any editor/engine specific code that was passing text to Slate as FString rather than FText.
[CL 2399803 by Jamie Dale in Main branch]
* Moved Slate.h into SlateBasics.h and began shifting less commonly used headers into SlateExtras.h.
* Slate.h now simply includes SlateBasics.h and SlateExtras.h.
* Slate.h includes a deprecated warning now to indicate that SlateBasics.h + specific includes should be used instead.
* Moved dozens of inlined functions using Slate widgets into .cpp files to avoid header dependencies.
* All code samples now include SlateBasics.h and SlateExtras.h so future shifts will not break most those projects, but not trigger the deprecation warning of including Slate.h.
#BUN
[CL 2329610 by Wes Hunt in Main branch]
