I had the strangest thing happen with this. I went to change the code line 623 as above and when I saved it in monodevelop, it deleted a number of lines of code. I undid the changes and tried to save what was there and it did it again. I tried this a few times to no avail. Every time monodevelop would delete about 800 or so lines of code.
I pulled it up in textpad and restored the file from a clipboard copy I made and saved it in it's original format, thinking I would test it first then make the edit on line 623 as above. When I tested it with the original code the error was gone.
I wonder if there were some special characters in the script that gave monodevelop and unity problems. Now that I saved it in an editor that stripped those out, everything works fine.