Rigify addon? WTG-bones? I am following this step from this link 

https://docs.unity3d.com/Manual/BlenderAndRigify.html

I am using blender 2.79 and the current vertion of "Rigify addon" I am not big fan of Addon for RIgging, I prefer manual , however I am working on a project and someone recommend me this addon...

It was nice up to this lines :


and the previous line (in the manual) it says , must delete all the wtg WGT-Bone, however If I delete all the wgt... there are not bones convections...at least not "DEF" ... welll I can not see my "bones names" in my propieties display....I only see  "rig:shoulder.L" , that is the prefix and sufix for bones...but they not appears in the propieties...(when I start the this rigify process, WTG appears in the propieties) , but I am triying to use my model for Unity ,so I must deleate the WTG-Bones from the propiety.... should I am wrong?.
Based on the "... to avoid having unassigned meshes" part of your screenshot, it looks like the manual is asking you to delete the widget (WGT) objects.

This is a collection of objects at the very last layer of the 3D view window. They aren't really bones, but meshes meant to be indexed as bone shapes to make them easier to identify.

If this doesn't work, you may have to delete both the widgets and remove the links to the widgets from the control bones. I hope not, that last bit will be tedious.

To delete the widget links, select a bone and go to Bone Properties >Display> Custom Shape and click the X. Do this for every bone.

I mention this last bit because Blender tends to save these custom shapes internally, so they can appear again even if the widget object is deleted.