Ignore existing ".dart.js" files.

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

Index: sdk/lib/_internal/pub/test/build/ignores_existing_compiled_js_files_test.dart
diff --git a/sdk/lib/_internal/pub/test/build/compiles_dart_entrypoints_to_js_test.dart b/sdk/lib/_internal/pub/test/build/ignores_existing_compiled_js_files_test.dart
similarity index 59%
copy from sdk/lib/_internal/pub/test/build/compiles_dart_entrypoints_to_js_test.dart
copy to sdk/lib/_internal/pub/test/build/ignores_existing_compiled_js_files_test.dart
index bc8319fed2ef461b3f439b4719408986c13ec0d4..7aecefef4e5166113336e8471c1a9069147a87ac 100644
--- a/sdk/lib/_internal/pub/test/build/compiles_dart_entrypoints_to_js_test.dart
+++ b/sdk/lib/_internal/pub/test/build/ignores_existing_compiled_js_files_test.dart
@@ -10,7 +10,7 @@ import '../test_pub.dart';
 main() {
   initConfig();
 
-  integration("compiles Dart entrypoints to JS", () {
+  integration("ignores existing JS files that were compiled to Dart", () {
     // Dart2js can take a long time to compile dart code, so we increase the
     // timeout to cope with that.
     currentSchedule.timeout *= 3;
@@ -19,31 +19,23 @@ main() {
       d.appPubspec(),
       d.dir('web', [
         d.file('file.dart', 'void main() => print("hello");'),
-        d.file('lib.dart', 'void foo() => print("hello");'),
+        d.file('file.dart.js', 'some js code'),
         d.dir('subdir', [
-          d.file('subfile.dart', 'void main() => print("ping");')
+          d.file('subfile.dart', 'void main() => print("ping");'),
+          d.file('subfile.dart.js', 'some js code')
         ])
       ])
     ]).create();
 
-    // TODO(rnystrom): If we flesh out the command-line output, validate that
-    // here.
     schedulePub(args: ["build"],
         output: new RegExp(r"Built 6 files!"),
         exitCode: 0);
 
     d.dir(appPath, [
       d.dir('build', [
-        d.matcherFile('file.dart.js', isNot(isEmpty)),
-        d.matcherFile('file.dart.precompiled.js', isNot(isEmpty)),
-        d.matcherFile('file.dart.js.map', isNot(isEmpty)),
-        d.nothing('file.dart'),
-        d.nothing('lib.dart'),
+        d.matcherFile('file.dart.js', isNot(equals('some js code'))),
         d.dir('subdir', [
-          d.matcherFile('subfile.dart.js', isNot(isEmpty)),
-          d.matcherFile('subfile.dart.precompiled.js', isNot(isEmpty)),
-          d.matcherFile('subfile.dart.js.map', isNot(isEmpty)),
-          d.nothing('subfile.dart')
+          d.matcherFile('subfile.dart.js', isNot(equals('some js code')))
         ])
       ])
     ]).validate();