Partial revert of #8250 as this is no longer a limitation

lib/ProvidePlugin.js

@@ -66,8 +66,9 @@ class ProvidePlugin {
 				normalModuleFactory.hooks.parser
 					.for("javascript/dynamic")
 					.tap("ProvidePlugin", handler);
-
-				// Disable ProvidePlugin for javascript/esm, see https://github.com/webpack/webpack/issues/7032
+				normalModuleFactory.hooks.parser
+					.for("javascript/esm")
+					.tap("ProvidePlugin", handler);
 			}
 		);
 	}

test/configCases/plugins/provide-plugin/esm.js

@@ -0,0 +1 @@
+module.exports = "esm";

test/configCases/plugins/provide-plugin/foo.mjs

@@ -1,3 +1,3 @@
 export default function foo() {
-    return typeof esm;
-}
+    return esm;
+}

test/configCases/plugins/provide-plugin/index.js

@@ -59,5 +59,5 @@ it("should provide ES2015 modules", function() {
 
 it("should not provide for mjs", function(){
 	var foo = require("./foo.mjs").default;
-	expect(foo()).toBe("undefined");
+	expect(foo()).toBe("esm");
 });

test/configCases/plugins/provide-plugin/webpack.config.js

@@ -11,7 +11,7 @@ module.exports = {
 			es2015_alias: ["./harmony", "alias"],
 			es2015_year: ["./harmony", "year"],
 			"this.aaa": "./aaa",
-			esm: "fail"
+			esm: "./esm"
 		})
 	]
 };