Fix type annotation and comment.

utils/pub/io.dart

Index: utils/pub/io.dart
diff --git a/utils/pub/io.dart b/utils/pub/io.dart
index 93e096b9dfc51cf45c9fdb97b875342ddefa3c31..1990aa28c9e4ec7f6a40ca5d36c9ab0ce917d1fb 100644
--- a/utils/pub/io.dart
+++ b/utils/pub/io.dart
@@ -608,7 +608,7 @@ Future<String> consumeStringInputStream(StringInputStream stream) {
 /// Wrap an InputStream in a ListInputStream. This eagerly drains the [source]
 /// input stream. This is useful for spawned processes which will not exit until
 /// their output streams have been drained.
-/// TODO(rnystrom): Get rid of this once #7218 is fixed.
+/// TODO(rnystrom): We should use this logic anywhere we spawn a process.
 InputStream wrapInputStream(InputStream source) {
   var sink = new ListInputStream();
   pipeInputToInput(source, sink);