src/vs/workbench/services/configuration/browser/configurationService.ts/WorkspaceService/compareFolders
class WorkspaceService:	private compareFolders(currentFolders: IWorkspaceFolder[], newFolders: IWorkspaceFolder[]): IWorkspaceFoldersChangeEvent {
		const result: IWorkspaceFoldersChangeEvent = { added: [], removed: [], changed: [] };
		result.added = newFolders.filter(newFolder => !currentFolders.some(currentFolder => newFolder.uri.toString() === currentFolder.uri.toString()));
		for (let currentIndex = 0; currentIndex < currentFolders.length; currentIndex++) {
			let currentFolder = currentFolders[currentIndex];
			let newIndex = 0;
			for (newIndex = 0; newIndex < newFolders.length && currentFolder.uri.toString() !== newFolders[newIndex].uri.toString(); newIndex++) { }
			if (newIndex < newFolders.length) {
				if (currentIndex !== newIndex || currentFolder.name !== newFolders[newIndex].name) {
					result.changed.push(currentFolder);
				}
			} else {
				result.removed.push(currentFolder);
			}
		}
		return result;
	}