Implement the V2 sandbox in the process launcher.

content/public/common/content_features.cc

Index: content/public/common/content_features.cc
diff --git a/content/public/common/content_features.cc b/content/public/common/content_features.cc
index 15fb85f6ab5ca9ed4a15758c954097dfafcf506a..4bd9c51033f981babc3110eac4826473c9cd5554 100644
--- a/content/public/common/content_features.cc
+++ b/content/public/common/content_features.cc
@@ -379,4 +379,9 @@ const base::Feature kWinSboxDisableExtensionPoints{
     "WinSboxDisableExtensionPoint", base::FEATURE_ENABLED_BY_DEFAULT};
 #endif
 
+#if defined(OS_MACOSX)
+const base::Feature kMacV2Sandbox{"MacV2Sandbox",

[Charlie Reis, 2017/06/17 20:07:59]

Can you document a bit about the V2 sandbox (e.g., maybe something about what's
new)?

+                                  base::FEATURE_DISABLED_BY_DEFAULT};
+#endif  // defined(OS_MACOSX)
+
 }  // namespace features