Enable sandbox in local discovery utility process.

content/public/common/content_switches.cc

Index: content/public/common/content_switches.cc
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 96ddf06f62ad99c4b221f546b68c5bd58a34a176..4436f97c22f3cdbb432ad9228d5d601e077f898d 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -791,6 +791,9 @@ const char kUtilityProcess[]                = "utility";
 // specifies the directory that can be accessed.
 const char kUtilityProcessAllowedDir[]      = "utility-allowed-dir";
 
+// Allows MDns to access network in sandboxed process.
+const char kUtilityProcessEnableMDns[]      = "utility-enable-mdns";
+
 // Will add kWaitForDebugger to every child processes. If a value is passed, it
 // will be used as a filter to determine if the child process should have the
 // kWaitForDebugger flag passed on or not.