Horizontal rules for Percentage Data Manipulation do not work when the Graph Item uses a CDEF

[TheWitness]

Describe the bug

Basically, any time the Graph Template Item that is being used in a Graph uses a CDEF, the Horizontal Rules on the Graph will not appear in the correct location.

To Reproduce
Steps to reproduce the behavior:

1. Create a Graph that uses a CDEF to display a value
2. Create a Threshold that uses the Percentage Data Manipulation Method
3. View the Graph with the Horizontal Rules enabled
4. Not the value is not correct or even visible

Expected behavior

Cacti should properly display the horizontal rule as modified by the CDEF if at all possible.

Additional context

This issue as are many others, is very old.