fix(infrastructure): add the es5 @material/package/dist/mdc.package t…

…o externals (#223)

packages/webpack.config.js

@@ -69,6 +69,7 @@ function getCommonWebpackParams(entryPath, chunk, {isCss, modules}) {
 }
 
 function getMaterialExternals() {
+  const dashedToCamel = (name) => name.replace(/-(\w)/g, (_, v) => v.toUpperCase());
   const externals = {};
   [
     'base',
@@ -86,7 +87,12 @@ function getMaterialExternals() {
     'textfield',
     'top-app-bar',
     'typography',
-  ].forEach((name) => externals[`@material/${name}`] = `@material/${name}`);
+  ].forEach((name) => {
+    // this can be reverted when we change back to @material/foo-package-filename
+    // https://github.com/material-components/material-components-web/pull/3245
+    const fileName = `@material/${name}/dist/mdc.${dashedToCamel(name)}`;
+    externals[fileName] = fileName;
+  });
   return externals;
 }