Fix incorrect desugaring of cascades.

tests/language/cascade_2_test.dart

Index: tests/language/cascade_2_test.dart
diff --git a/tests/language/cascade_2_test.dart b/tests/language/cascade_2_test.dart
index 7ec06f9afa3f3288eaace2dcbcb51111e121ef03..2675f61ac546e7f9663951f2ca13b10f9690779a 100644
--- a/tests/language/cascade_2_test.dart
+++ b/tests/language/cascade_2_test.dart
@@ -2,15 +2,17 @@
 // 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.
 
-// Test cascades, issue 7665.
+// Test cascades, issues 7494 (vm), 7689 (dart2js).
 
 main() {
   var a = new Element(null);
   Expect.equals(1, a.path0.length);
   Expect.equals(a, a.path0[0]);
 
-  Expect.equals(1, a.path1.length);  // 2 instead of 1
+  // Issue 7693: e0 ? e1 : e2..f() parses as (e0 ? e1 : e2)..f().
+  Expect.equals(2, a.path1.length);
   Expect.equals(a, a.path1[0]);
+  Expect.equals(a, a.path1[1]);
 
   Expect.equals(1, a.path2.length);  // NPE.
 
@@ -19,9 +21,10 @@ main() {
   Expect.equals(a, b.path0[0]);
   Expect.equals(b, b.path0[1]);
 
-  Expect.equals(2, b.path1.length);  // 3 instead of 2.
+  Expect.equals(3, b.path1.length);
   Expect.equals(a, b.path1[0]);
-  Expect.equals(b, b.path1[1]);
+  Expect.equals(a, b.path1[1]);
+  Expect.equals(b, b.path1[2]);
 
   Expect.equals(2, b.path2.length);  // NPE.
 }