The clock is ticking. Gov. Gavin Newsom has until Wednesday to decide on a bill that would make California the first state in the nation to require water suppliers who monitor a broad class of toxic “forever chemicals” to notify customers if they’re present in drinking water. “A decision will come tomorrow,” a spokesman for Newsom said Tuesday. He declined to say what it would be. The PFAS chemicals, which have been widely used in everything from firefighting foam to Teflon pans, Scotchgard products and even some dental floss, have been linked in some research to cancers, developmental problems and thyroid and liver disease. They’re known as “forever chemicals” because they don’t break down in the environment or in human bodies.