:OnRequestContextInitialized is called. Request context preferences are registered each time a new cef_request_context_t is created. It is intended but not required that all request contexts have the same registered preferences. See related cef_request_context_settings_t.cache_path and cef_request_context_settings_t.persist_user_preferences configuration.
Do not keep a reference to the |registrar| object. This function is called on the browser process UI thread.
cef_settings_t.persist_user_preferences configuration.
If |type| is CEF_PREFERENCES_TYPE_REQUEST_CONTEXT the preferences can be accessed via the cef_request_context_t after