Fix cpplint errors in browser_client.h
Fix cpplint errors in browser_client.h

bbondy/brightray,lakshmi-srinivas/brightray,lakshmi-srinivas/brightray,tejaspathak/brightray,tejaspathak/brightray,hokein/brightray,paulcbetts/brightray,atom/brightray,paulcbetts/brightray,deepak1556/brightray,bbondy/brightray,hokein/brightray,brave/brightray,lakshmi-srinivas/brightray,deepak1556/brightray,brave/brightray,atom/brightray