UCanvasPanelSlot::PostEditChangeChainProperty does not call Super function

UCanvasPanelSlot::PostEditChangeChainProperty not only does not call its Super function unless the anchor node has been set, but it calls Super:: PostEditChangeProperty instead PostEditChainProperty.

Tested in 4.19.2 (CL - 4033788), 4.20.3 (CL - 4369336), 4.21.1 (CL - 4541578), 4.22 (CL - 4562192)

1. Open or create a UE4 C++ project
2. Navigate to CanvasPanelSlot.cpp 
3. Inspect the PostEditChainProperty void function

Expected: The function would always call its Super function 

Result: The overrided function only calls its Super function when the anchor nodes have been set, even then it calls PostEditChangeProperty instead of PostEditChainProperty