Store the async-await compiled pub code directly in the repo.

sdk/lib/_internal/pub_generated/test/transformer/loads_a_diamond_transformer_dependency_graph_test.dart

+library pub_tests;
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+import '../serve/utils.dart';
+main() {
+  initConfig();
+  withBarbackVersions("any", () {
+    integration("loads a diamond transformer dependency graph", () {
+      d.dir("top", [d.pubspec({
+          "name": "top",
+          "version": "1.0.0"
+        }),
+            d.dir("lib", [d.file("transformer.dart", dartTransformer('top'))])]).create();
+      d.dir("left", [d.pubspec({
+          "name": "left",
+          "version": "1.0.0",
+          "transformers": ["top/transformer"],
+          "dependencies": {
+            "top": {
+              "path": "../top"
+            }
+          }
+        }),
+            d.dir("lib", [d.file("transformer.dart", dartTransformer('left'))])]).create();
+      d.dir("right", [d.pubspec({
+          "name": "right",
+          "version": "1.0.0",
+          "transformers": ["top/transformer"],
+          "dependencies": {
+            "top": {
+              "path": "../top"
+            }
+          }
+        }),
+            d.dir("lib", [d.file("transformer.dart", dartTransformer('right'))])]).create();
+      d.dir(appPath, [d.pubspec({
+          "name": "myapp",
+          "transformers": [
+              "left/transformer",
+              "right/transformer",
+              "myapp/transformer"],
+          "dependencies": {
+            'left': {
+              'path': '../left'
+            },
+            'right': {
+              'path': '../right'
+            }
+          }
+        }),
+            d.dir("lib", [d.file("transformer.dart", dartTransformer('myapp'))]),
+            d.dir("web", [d.file("main.dart", 'const TOKEN = "main.dart";')])]).create();
+      createLockFile(
+          'myapp',
+          sandbox: ['top', 'left', 'right'],
+          pkg: ['barback']);
+      pubServe();
+      requestShouldSucceed(
+          "main.dart",
+          'const TOKEN = "(((main.dart, (left, top)), (right, top)), ((myapp, '
+              '(left, top)), (right, top)))";');
+      endPubServe();
+    });
+  });
+}