public void registerCompletionProviders(final AceEditorMode aceEditorMode,
                                            final AceCompletionProvider... completionProviders) {
        registerCompletionProviders(null, aceEditorMode, completionProviders);
    }
Register editor instance agnostic completion providers specific to a mode
stroom-core-client-widget/src/main/java/stroom/editor/client/presenter/DelegatingAceCompleter.java