The erase mode has an option to change the erase mode from soft/hard/stroke.
However, there are 4 brush types: hard/soft/point/stroke. Hard and Soft here are similar (they are both "soft" erase mode) only having different strengths.
The erase mode should be soft (Maybe this should be renamed to something more generic like "fade"), point, stroke.
Reviewed By: #user_interface, #grease_pencil, billreynish, antoniov
Differential Revision: https://developer.blender.org/D6733
057b78c40c