Lately, I've noticed the addition of "/webhp" in the url of Google searches along with some additional variables, "sourceid", "rlz", and a few others. Together, they make a URL in the form of https://www.google.com/webhp/...
In addition, this only happens when searching from the Omnibox. Going to google.com and searching with the input field within the page creates a different URL.
Is this the result of some sort of virus? I've seen explanations for both sides. The explanations toward the malicious end suggest that it's because of the (possibly unintentional) installation of a "Conduit" search toolbar.
At any rate, I've checked all of my cookies, extensions, toolbars (none), registry, and installed programs as directed by various removal sites but nothing seems to suggest that I have this "Conduit" search bar or anything related.
Windows 7, Chrome 38