Add Link.copyWithout.

dart/tests/compiler/dart2js/link_test.dart

Index: dart/tests/compiler/dart2js/link_test.dart
diff --git a/dart/tests/compiler/dart2js/link_test.dart b/dart/tests/compiler/dart2js/link_test.dart
index a2c21222e6264851e0d70b9ff0f619a4c5ad25bb..5ee61e4ba0068a091b6f6c4ed06682a3e50f78fe 100644
--- a/dart/tests/compiler/dart2js/link_test.dart
+++ b/dart/tests/compiler/dart2js/link_test.dart
@@ -21,6 +21,8 @@ main() {
   testFromList([0, 1, 2, 3, 4]);
   testFromList([0, 1, 2, 3, 4, 5]);
   testSkip();
+
+  testCopyWithout();
 }
 
 testFromList(List list) {
@@ -61,3 +63,14 @@ testSkip() {
   Expect.isTrue(emptyLink.skip(0).isEmpty);
   Expect.throws(() => emptyLink.skip(1), (e) => e is RangeError);
 }
+
+testCopyWithout() {
+  test(const Link().copyWithout(0), []);
+
+  test(LinkFromList([0]).copyWithout(0), []);
+  test(LinkFromList([0, 1]).copyWithout(0), [1]);
+  test(LinkFromList([0, 1, 2]).copyWithout(0), [1, 2]);
+  test(LinkFromList([0, 1, 2]).copyWithout(1), [0, 2]);
+  test(LinkFromList([0, 1, 2]).copyWithout(2), [0, 1]);
+  test(LinkFromList([0, 1, 2]).copyWithout(3), [0, 1, 2]);
+}