Make sequence-zip test not be timing dependent.

pkg/sequence_zip/test/stream_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import "dart:async";
 import "package:sequence_zip/stream_zip.dart";
 import "package:unittest/unittest.dart";
 
 /// Create an error with the same values as [base], except that it throwsA
 /// when seeing the value [errorValue].
@@ skipping 123 matching lines @@
                 [streamError(mks([1, 2, 3, 4]), 4),
                  (new StreamController()..add(4)..add(5)..add(6)).stream,
                  (new StreamController()..add(7)..add(8)..add(9)).stream]
                ).toList(),
            throwsA(equals("BAD")));
   });
 
   test("Error after first end", () {
     StreamController controller = new StreamController();
     controller..add(7)..add(8)..add(9);
-    testZip([mks([1, 2, 3]),
-             mks([4, 5, 6]),
+    int ctr = 2;
+    Function addErrorIf(x) {
+      return (y) {
+        // Adds error to controller after both of the first two streams have
+        // provided all three elements.
+        if (x == y && --ctr == 0) Timer.run(() { controller.addError("BAD"); });
+        return y;
+      };
+    }
+    testZip([mks([1, 2, 3].map(addErrorIf(3))),
+             mks([4, 5, 6].map(addErrorIf(6))),
              controller.stream],
            [[1, 4, 7], [2, 5, 8], [3, 6, 9]]);
-    // This comes after the first three events in all cases, since they
-    // use durations no greater than 10 ms.
-    new Timer(const Duration(milliseconds: 100), () {
-      controller.addError("BAD");
-    });
   });
 
   test("Pause/Resume", () {
     var done = expectAsync0((){});  // Call to complete test.
 
     int sc1p = 0;
     StreamController c1 = new StreamController(
       onPause: () {
         sc1p++;
       },
@@ skipping 57 matching lines @@
       } else if (ctr == 2) {
         sub.pause();
         new Future.delayed(const Duration(milliseconds: 25)).then((_) {
           sub.resume();
         });
       }
       ctr++;
     }, count: 4));
   });
 }