System Information
Operating system: Windows-10-10.0.17763 64 Bits
Graphics card: Quadro M4000/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 391.25

Blender Version
Broken: version: 2.80 (sub 59), branch: blender2.7, commit date: 2019-04-24 22:25, hash: rBd966c2f0c2ad
Worked: (optional)

Short description of error
When changing the editor type in an area, the info panel often prints an incorrect readout of how the
bpy.context.area.ui_type has been changed

for example when changing an area to the ShaderNodeTree the info panel reads:

bpy.context.area.ui_type = 'TextureNodeTree'

and many area changes read:

bpy.context.area.ui_type = '<UNKNOWN ENUM>'

Exact steps for others to reproduce the error
Open blender
Go to 'Scripting' layout
Change the area type of the text editor to the shader editor
observe the 'info' area for readout of the ui type change, which should be incorrect