ComponentCloudPolicyService tracks the signin state.

components/policy/core/common/policy_switches.cc

Index: components/policy/core/common/policy_switches.cc
diff --git a/components/policy/core/common/policy_switches.cc b/components/policy/core/common/policy_switches.cc
index a55ea6a68c2c872ddfc35452ce980a466572d18b..9b7261fff6991b1159023b43b9667e02291c3506 100644
--- a/components/policy/core/common/policy_switches.cc
+++ b/components/policy/core/common/policy_switches.cc
@@ -16,6 +16,10 @@ const char kCloudPolicyInvalidationDelay[]  = "cloud-policy-invalidation-delay";
 // Disables pushing cloud policy to Chrome using an invalidation service.
 const char kDisableCloudPolicyPush[]        = "disable-cloud-policy-push";
 
+// Enables fetching and storing cloud policy for components. This currently
+// supports policy for extensions on Chrome OS.
+const char kEnableComponentCloudPolicy[]    = "enable-component-cloud-policy";
+
 #if defined(OS_ANDROID) || defined(OS_IOS)
 // Registers for cloud policy using the BROWSER client type instead of the
 // ANDROID_BROWSER or IOS_BROWSER types.