src/vs/workbench/contrib/preferences/browser/keybindingsEditor.ts/KeybindingsEditor/createDefineWhenExpressionAction
class KeybindingsEditor:	private createDefineWhenExpressionAction(keybindingItemEntry: IKeybindingItemEntry): IAction {
		return <IAction>{
			label: localize('editWhen', "Change When Expression"),
			enabled: !!keybindingItemEntry.keybindingItem.keybinding,
			id: KEYBINDINGS_EDITOR_COMMAND_DEFINE_WHEN,
			run: () => this.defineWhenExpression(keybindingItemEntry)
		};
	}