mac: Fix blank page after devtools is opened.
mac: Fix blank page after devtools is opened.

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