Show modal dialog to tell users that the profile is managed when it's the case.

chrome/common/extensions/api/developer_private.idl

Index: chrome/common/extensions/api/developer_private.idl
diff --git a/chrome/common/extensions/api/developer_private.idl b/chrome/common/extensions/api/developer_private.idl
index 3a17d0597d5475eec6beff1a0ce0f962a3367a68..57307e3791961eb4a02017967a3d02a9e8594f1a 100644
--- a/chrome/common/extensions/api/developer_private.idl
+++ b/chrome/common/extensions/api/developer_private.idl
@@ -204,6 +204,9 @@ namespace developerPrivate {
     // strings as a dictionary mapping from string identifier to the
     // translated string to use in the apps_debugger app UI.
     static void getStrings(GetStringsCallback callback);
+
+    // Returns true if the profile is managed.
+    static void isProfileManaged(BooleanCallback callback);
   };
 
   interface Events {