Sure, but it matters
why Google is funding them. Google funds Mozilla in order to keep them afloat as a foil to detract from antitrust scrutiny. That's only credible if Google
does not exert any kind of pressure over them as a condition for that funding. If they did exert that kind of pressure, it would completely defeat the purpose of funding them in the first place.
So I don't consider that to create a conflict of interest.