Add new ExtensionManagement preference

extensions/browser/pref_names.h

Index: extensions/browser/pref_names.h
diff --git a/extensions/browser/pref_names.h b/extensions/browser/pref_names.h
index e552455ed2c31ba107377ea0771f190845c4e0d6..e221c35cc97b37bf100f5e2b14ccbc5a575b9b09 100644
--- a/extensions/browser/pref_names.h
+++ b/extensions/browser/pref_names.h
@@ -47,6 +47,11 @@ extern const char kBookmarkAppCreationLaunchType[];
 // extension ids.
 extern const char kExtensions[];
 
+// Dictionary pref that manages extensions, controlled by policy.
+// Values are expected to conform to the schema of the ExtensionManagement
+// policy.
+extern const char kExtensionManagement[];
+
 // A whitelist of extension ids the user can install: exceptions from the
 // following blacklist.
 extern const char kInstallAllowList[];