Tweak corelib/ConstListLiteralTest while we wait for a resolution of CL 9839101.

dart/frog/leg/lib/js_helper.dart

Index: dart/frog/leg/lib/js_helper.dart
diff --git a/dart/frog/leg/lib/js_helper.dart b/dart/frog/leg/lib/js_helper.dart
index 2514d09f692ab2e053713eb526c46fe70f5161b6..c9997e803939b49137ed74bafd04a0240fcab3cd 100644
--- a/dart/frog/leg/lib/js_helper.dart
+++ b/dart/frog/leg/lib/js_helper.dart
@@ -1368,11 +1368,3 @@ class Null {
 }
 
 builtin$get$toString(receiver) => () => builtin$toString$0(receiver);
-
-builtin$copyFrom$4(receiver, arg1, arg2, arg3, arg4) {
-  // TODO(ahe): Remove this method when CL 9839101 has landed.
-  if (!isJsArray(receiver)) {
-    return UNINTERCEPTED(receiver.copyFrom(arg1, arg2, arg3, arg4));
-  }
-  throw new UnsupportedOperationException('copyFrom');
-}