[Policy Experimental] Add "recommended" policies for URL exceptions.

components/prefs/pref_service.h

Index: components/prefs/pref_service.h
diff --git a/components/prefs/pref_service.h b/components/prefs/pref_service.h
index 6c95b64f6536eb1e8174bb097bda4b71bfa31099..06ad39907d99868251ce9daae1103f599cf56fa7 100644
--- a/components/prefs/pref_service.h
+++ b/components/prefs/pref_service.h
@@ -83,6 +83,9 @@ class COMPONENTS_PREFS_EXPORT PrefService : public base::NonThreadSafe {
     // default value if no other has been set.
     const base::Value* GetValue() const;
 
+    // Returns the value managed by the admin, if any.
+    const base::Value* GetManagedValue() const;
+
     // Returns the value recommended by the admin, if any.
     const base::Value* GetRecommendedValue() const;