Support directories other than "web" in pub build.

sdk/lib/_internal/pub/test/build/ignores_entrypoints_in_asset_test.dart

Index: sdk/lib/_internal/pub/test/build/ignores_entrypoints_in_asset_test.dart
diff --git a/sdk/lib/_internal/pub/test/build/ignores_entrypoints_in_asset_test.dart b/sdk/lib/_internal/pub/test/build/ignores_entrypoints_in_asset_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..27fd0821758a50901bee90bffd7e8fd0e83c9f10
--- /dev/null
+++ b/sdk/lib/_internal/pub/test/build/ignores_entrypoints_in_asset_test.dart
@@ -0,0 +1,34 @@
+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+
+main() {
+  initConfig();
+
+  integration("ignores entrypoint Dart files in asset/", () {
+    d.dir(appPath, [
+      d.appPubspec(),
+      d.dir('asset', [
+        d.file('file.dart', 'void main() => print("hello");'),
+      ]),
+      d.dir('web', [
+        d.file('index.html', 'html'),
+      ])
+    ]).create();
+
+    schedulePub(args: ["build", "--all"],
+        output: new RegExp(r"Built 1 file!"));
+
+    d.dir(appPath, [
+      d.dir('build', [
+        d.nothing('asset'),
+        d.dir('web', [
+          d.file('index.html', 'html')
+        ])
+      ])
+    ]).validate();
+  });
+}