Add flags for v2 sandbox to Chrome and Helper executable.

content/common/sandbox_init_mac.cc

Index: content/common/sandbox_init_mac.cc
diff --git a/content/common/sandbox_init_mac.cc b/content/common/sandbox_init_mac.cc
index 36a4058c35e3a5f449f5704629dad98117fd86a3..b63600becf012d364ea8284cae2e19c2b1b0c3a3 100644
--- a/content/common/sandbox_init_mac.cc
+++ b/content/common/sandbox_init_mac.cc
@@ -10,6 +10,7 @@
 #include "content/common/sandbox_mac.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/sandbox_init.h"
+#include "sandbox/mac/seatbelt.h"
 
 namespace content {
 
@@ -36,6 +37,8 @@ bool GetSandboxTypeFromCommandLine(int* sandbox_type,
       *base::CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(switches::kNoSandbox))
     return false;
+  if (command_line.HasSwitch(switches::kV2SandboxedEnabled))
+    CHECK(sandbox::Seatbelt::IsSandboxed());
 
   std::string process_type =
       command_line.GetSwitchValueASCII(switches::kProcessType);