feat: make the minimizer config available in all modes (#4641)

As long as the `minimize` option is set to false (which is default in
production mode), the code won't be minimized. So the mode doesn't
matter when it comes to the `minimizer` config.

By exposing this config, users can simplify their custom config, by
removing the `process.env.NODE_ENV === 'production'` guard around their
custom minimizer configuration.

packages/@vue/cli-service/lib/config/base.js

@@ -187,5 +187,11 @@ module.exports = (api, options) => {
           additionalTransformers: [transformer],
           additionalFormatters: [formatter]
         }])
+
+    const TerserPlugin = require('terser-webpack-plugin')
+    const terserOptions = require('./terserOptions')
+    webpackConfig.optimization
+      .minimizer('terser')
+        .use(TerserPlugin, [terserOptions(options)])
   })
 }

packages/@vue/cli-service/lib/config/prod.js

@@ -15,12 +15,6 @@ module.exports = (api, options) => {
       // disable optimization during tests to speed things up
       if (process.env.VUE_CLI_TEST) {
         webpackConfig.optimization.minimize(false)
-      } else {
-        const TerserPlugin = require('terser-webpack-plugin')
-        const terserOptions = require('./terserOptions')
-        webpackConfig.optimization
-          .minimizer('terser')
-            .use(TerserPlugin, [terserOptions(options)])
       }
     }
   })