Remove the wrapStream workaround for issue 8310.

utils/tests/pub/test_pub.dart

Index: utils/tests/pub/test_pub.dart
diff --git a/utils/tests/pub/test_pub.dart b/utils/tests/pub/test_pub.dart
index b0d973a69a793af3cbf0dbb7675fe2c7cd96f01e..9ee04034ffa208f251a704aaba47cb3bfa10348c 100644
--- a/utils/tests/pub/test_pub.dart
+++ b/utils/tests/pub/test_pub.dart
@@ -1315,10 +1315,9 @@ class ScheduledProcess {
       _process = p;
 
       byteStreamToLines(stream) {
-        var handledErrors = wrapStream(stream.handleError((e) {
+        return streamToLines(new ByteStream(stream.handleError((e) {
           registerException(e.error, e.stackTrace);
-        }));
-        return streamToLines(new ByteStream(handledErrors).toStringStream());
+        })).toStringStream());
       }
 
       var stdoutTee = tee(byteStreamToLines(p.stdout));