Upgrade Rollup build process

package.json

@@ -61,12 +61,16 @@
     "object-is": "^1.1.2"
   },
   "devDependencies": {
+    "@ampproject/rollup-plugin-closure-compiler": "^0.25.2",
     "@babel/core": "^7.9.0",
     "@babel/plugin-transform-flow-strip-types": "^7.9.0",
     "@babel/plugin-transform-object-assign": "^7.8.3",
     "@babel/preset-env": "^7.9.5",
     "@babel/preset-flow": "^7.9.0",
     "@babel/preset-react": "^7.9.4",
+    "@rollup/plugin-buble": "^0.21.3",
+    "@rollup/plugin-commonjs": "^11.1.0",
+    "@rollup/plugin-node-resolve": "^7.1.3",
     "babel-plugin-closure-elimination": "^1.3.0",
     "babel-plugin-transform-async-to-promises": "^0.8.15",
     "codecov": "^3.6.5",
@@ -81,9 +85,6 @@
     "react-is": "^16.13.1",
     "rollup": "^2.6.1",
     "rollup-plugin-babel": "^4.4.0",
-    "rollup-plugin-buble": "^0.19.8",
-    "rollup-plugin-commonjs": "^10.1.0",
-    "rollup-plugin-node-resolve": "^5.2.0",
     "rollup-plugin-replace": "^2.2.0",
     "rollup-plugin-terser": "^5.3.0"
   }

rollup.config.js

@@ -1,8 +1,9 @@
-import commonjs from 'rollup-plugin-commonjs'
-import nodeResolve from 'rollup-plugin-node-resolve'
-import buble from 'rollup-plugin-buble'
+import commonjs from '@rollup/plugin-commonjs'
+import nodeResolve from '@rollup/plugin-node-resolve'
+import buble from '@rollup/plugin-buble'
 import babel from 'rollup-plugin-babel'
 import { terser } from 'rollup-plugin-terser'
+import compiler from '@ampproject/rollup-plugin-closure-compiler'
 import replace from 'rollup-plugin-replace'
 
 const pkgInfo = require('./package.json')
@@ -19,7 +20,7 @@ if (pkgInfo.dependencies) {
 }
 
 const externalPredicate = new RegExp(`^(${external.join('|')})($|/)`)
-const externalTest = id => {
+const externalTest = (id) => {
   if (id === 'babel-plugin-transform-async-to-promises/helpers') {
     return false
   }
@@ -117,6 +118,10 @@ const makePlugins = (isProduction = false) => [
     replace({
       'process.env.NODE_ENV': JSON.stringify('production')
     }),
+  isProduction &&
+    compiler({
+      compilation_level: 'SIMPLE_OPTIMIZATIONS'
+    }),
   isProduction ? terserMinified : terserPretty
 ]