[Windows Sandbox] Turn on MITIGATION_EXTENSION_POINT_DISABLE for child processes.

content/public/common/BUILD.gn

Index: content/public/common/BUILD.gn
diff --git a/content/public/common/BUILD.gn b/content/public/common/BUILD.gn
index ae955f656c54eb6c4fddbdb01e76ca829f51d502..2df12fd39bbb5bfbf5d3dd81c79526ca8985a600 100644
--- a/content/public/common/BUILD.gn
+++ b/content/public/common/BUILD.gn
@@ -68,6 +68,24 @@ source_set("static_switches") {
   public_configs = [ ":static_switches_defines" ]
 }
 
+# This target allows you to use the content_features constants and statically
+# link to it, without depending on the rest of content. This is only for use
+# without content, or you will get multiply defined symbols.
+source_set("static_features") {
+  public = [
+    "content_features.h",
+  ]
+  sources = [
+    "//content/common/content_export.h",
+    "content_features.cc",
+  ]
+  public_deps = [
+    "//base",
+  ]
+
+  public_configs = [ ":static_switches_defines" ]
+}
+
 source_set("common_sources") {
   # External code should depend on via ":common" above.
   visibility = [ "//content/*" ]