That's Eclipse telling you that you tried to debug into third party code. You have the binary code jar available, but not the source code jar.
If you are using Maven, this usually gets downloaded automatically after a few seconds. If you are just using a standalone project, you'll need to download the source jar yourself. Then in the project build properties, there is an option to identify the location of the source jar.
Alternatively, you could just step past the third party code and get back to your code. After all, your bug is much more likely to be in your code than in Selenium itself.
Appreciated. When I was debugging with someone watching the process he said to just step past this error. I did not realize that I could keep moving forward. Now I know why he said to keep debugging. I thought that I was at completely dead spot in the debug but I was not.