Using the old DOF algorithm doesn't work properly

When using CircleDOF with the old algorithm it will not properly blur objects close to the camera. 

Working properly in 4.19 CL# 4033788

Found in 4.20 Preview 2 CL# 4121666 and 4.21 CL# 4131780

This is a regression.

1. Open the editor
2. Create a new project with starter content
3. Go to project settings and uncheck "Use new DOF algorithm"
4. Select the post processing volume in the startup level
5. Set depth of field method to CircleDOF and Aperture to 1
6. Move close enough to the floor that it should be out of focus

Results:
The DOF will not cause the floor or an close objects to be properly out of focus

Expected:
The floor will be out of focus like in 4.19