module: improve support of data: URLs

Add support for loading modules using percent-encoded URLs.

Author: aduh95

lib/internal/modules/esm/get_source.js

@@ -32,7 +32,7 @@ async function defaultGetSource(url, { format } = {}, defaultGetSource) {
       throw new ERR_INVALID_URL(url);
     }
     const { 1: base64, 2: body } = match;
-    source = Buffer.from(body, base64 ? 'base64' : 'utf8');
+    source = Buffer.from(decodeURIComponent(body), base64 ? 'base64' : 'utf8');
   } else {
     throw new ERR_INVALID_URL_SCHEME(['file', 'data']);
   }

test/es-module/test-esm-data-urls.js

@@ -102,4 +102,9 @@ function createBase64URL(mime, body) {
       assert.strictEqual(e.code, 'ERR_INVALID_RETURN_PROPERTY_VALUE');
     }
   }
+  {
+    const plainESMURL = 'data:text/javascript,export%20default%202';
+    const module = await import(plainESMURL);
+    assert.strictEqual(module.default, 2);
+  }
 })().then(common.mustCall());