The European Commission has given Procter & Gamble Co. permission to take over German hair care group Wella, the U.S. group’s largest deal ever, a source familiar with the situation said on Tuesday.P&G, the leading U.S. consumer products company whose products include Tide detergent and Herbal Essences shampoo, has said the deal moves it into the $10 billion salon products business and strengthens its coloring and styling products business in Europe. The source told Reuters that ...