This is certainly distribution.
If the `checkBrowser` function uses GPL'd code, then anything that calls `checkBrowser` in turn must be licensed under the GPL.
But that doesn't mean that this Comcast code _is_ licensed under the GPL. That means that the copyright owner (brainjar) can take action against Comcast, and tell them to either stop using their code, or change the license.
They'd just stop using the code.