function (oldContext, newContext) {
            var changes = [];

            _.each(this._scopes, function (scope) {
                var changedInScope = scope.contextChanged(oldContext, newContext);
                if (changedInScope) {
                    changes.push(changedInScope);
                }
            });

            changes = _.union.apply(null, changes);
            if (changes.length > 0) {
                this._triggerChange({
                    ids: changes
                });
            }
        }
function (oldContext, newContext) {
            var changes = [];

            _.each(this._scopes, function (scope) {
                var changedInScope = scope.contextChanged(oldContext, newContext);
                if (changedInScope) {
                    changes.push(changedInScope);
                }
            });

            changes = _.union.apply(null, changes);
            if (changes.length > 0) {
                this._triggerChange({
                    ids: changes
                });
            }
        }
function ( oldContext , newContext ) { var changes = [ ] ; _ . each ( this . _scopes , function ( scope ) { var changedInScope = scope . contextChanged ( oldContext , newContext ) ; if ( changedInScope ) { changes . push ( changedInScope ) ; } } ) ; changes = _ . union . apply ( null , changes ) ; if ( changes . length > 0 ) { this . _triggerChange ( { ids : changes } ) ; } }
Signals the context change to all the scopes within the preferences
layer.  PreferencesManager is in charge of computing the context and
signaling the changes to PreferencesSystem.

@param {{path: string, language: string}} oldContext Old context
@param {{path: string, language: string}} newContext New context
Signals the context change to all the scopes within the preferences layer . PreferencesManager is in charge of computing the context and signaling the changes to PreferencesSystem .
trigger contextChanged event