Don't propagate synchronous Future.wait errors immediately.

tests/lib/async/future_test.dart

Index: tests/lib/async/future_test.dart
diff --git a/tests/lib/async/future_test.dart b/tests/lib/async/future_test.dart
index 71c509b6fd3973e7790df4418d8b1e55dd7bcb72..9c8dc7e44af1f5544a567d271e18b37b64639a2a 100644
--- a/tests/lib/async/future_test.dart
+++ b/tests/lib/async/future_test.dart
@@ -879,7 +879,6 @@ void testWaitCleanUpError() {
 void testWaitSyncError() {
   var cms = const Duration(milliseconds: 100);
   var cleanups = new List.filled(3, false);
-  var uncaughts = new List.filled(3, false);
   asyncStart();
   asyncStart();
   runZoned(() {
@@ -896,6 +895,18 @@ void testWaitSyncError() {
   });
 }
 
+void testWaitSyncError2() {
+  asyncStart();
+  Future.wait([null]).catchError((e, st) {
+    // Makes sure that the `catchError` is invoked.
+    // Regression test: an earlier version of `Future.wait` would propagate
+    // the error too soon for the code to install an error handler.
+    // `testWaitSyncError` didn't show this problem, because the `runZoned`
+    // was already installed.
+    asyncEnd();
+  });
+}
+
 void testBadFuture() {
   var bad = new BadFuture();
   // Completing with bad future (then call throws) puts error in result.
@@ -1096,6 +1107,7 @@ main() {
   testWaitCleanUp();
   testWaitCleanUpError();
   testWaitSyncError();
+  testWaitSyncError2();
 
   testBadFuture();