I realized that the code associated with these two CLI modules BlobDetection and ConnectedComponent have NOT been compiled since r20744 (from August 2010).
The commit message indicates:
ENH: remove BlobDetection and other CLI modules as requested
Associated issue was:
#2809: Create extensions for BlobDetection and ConnectedComponent module
And a excerpt from @pieper reply from on the slicer-devel mailing list thread entitled Re: Adding new modules to Slicer core? :
Based on the information I found, I will submit a PR removing the modules today and plan on integrating it tomorrow.