Output all files generated by dart2js, not just the main one.

sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart

Index: sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart
diff --git a/sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart b/sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart
index 0778ab15ab8fe600e971e9156f508a44fbffa5c2..fd8a7ac9d8c45fe5e7215a6a01ea51e17983b931 100644
--- a/sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart
+++ b/sdk/lib/_internal/pub/test/build/dart2js_finds_imports_across_packages_test.dart
@@ -47,12 +47,14 @@ main() {
     ]).create();
 
     schedulePub(args: ["build"],
-        output: new RegExp(r"Built 1 file!"),
+        output: new RegExp(r"Built 3 files!"),
         exitCode: 0);
 
     d.dir(appPath, [
       d.dir('build', [
-        d.matcherFile('main.dart.js', isNot(isEmpty))
+        d.matcherFile('main.dart.js', isNot(isEmpty)),
+        d.matcherFile('main.dart.precompiled.js', isNot(isEmpty)),
+        d.matcherFile('main.dart.js.map', isNot(isEmpty))
       ])
     ]).validate();
   });