pkg/test: Resolve a number of analyzer warnings

lib/src/runner/browser/dartium.dart

Index: lib/src/runner/browser/dartium.dart
diff --git a/lib/src/runner/browser/dartium.dart b/lib/src/runner/browser/dartium.dart
index 1d829bc0f52bcbb39ec6b5225e4c2e3415070135..16c74a17fb5199c33f3d3df42e3d6432cc6b590b 100644
--- a/lib/src/runner/browser/dartium.dart
+++ b/lib/src/runner/browser/dartium.dart
@@ -113,7 +113,7 @@ class Dartium extends Browser {
   /// the Observatory instance that actually contains an isolate, and returning
   /// the corresponding URI.
   static Future<Uri> _getObservatoryUrl(Stream<List<int>> stdout) async {
-    var urlQueue = new StreamQueue<Uri>(lineSplitter.bind(stdout).map((line) {
+    var urlQueue = new StreamQueue<Uri>(transformUtf8ToLines(stdout).map((line) {
       var match = _observatoryRegExp.firstMatch(line);
       return match == null ? null : Uri.parse(match[1]);
     }).where((line) => line != null));