fix: use .needsDifferentialLoading instead of .module

Because we now automatically skips differential loading if all targets support es module, regardless of the `.module` flag

Author: haoqunjiang

packages/@vue/cli-service/lib/commands/build/index.js

@@ -64,6 +64,7 @@ module.exports = (api, options) => {
  needsDifferentialLoading = false
  }
 
+ args.needsDifferentialLoading = needsDifferentialLoading
  if (!needsDifferentialLoading) {
  await build(args, api, options)
  return
@@ -109,7 +110,7 @@ async function build (args, api, options) {
  log()
  const mode = api.service.mode
  if (args.target === 'app') {
- const bundleTag = args.module
+ const bundleTag = args.needsDifferentialLoading
  ? args.moduleBuild
  ? `module bundle `
  : `legacy bundle `
@@ -131,7 +132,7 @@ async function build (args, api, options) {
  }
 
  const targetDir = api.resolve(options.outputDir)
- const isLegacyBuild = args.target === 'app' && args.module && !args.moduleBuild
+ const isLegacyBuild = args.needsDifferentialLoading && !args.moduleBuild
 
  // resolve raw webpack config
  let webpackConfig