Add a parameter to return continuations

sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart

Index: sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart
diff --git a/sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart b/sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart
index cd6d3aaa3e1bba9106b20579f45113d3aa8f2448..83c15992123a08a58f5337b88bb7abdc7c73698a 100644
--- a/sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart
+++ b/sdk/lib/_internal/compiler/implementation/cps_ir/cps_ir_nodes.dart
@@ -494,8 +494,8 @@ class Parameter extends Primitive {
   accept(Visitor visitor) => visitor.visitParameter(this);
 }
 
-/// Continuations are normally bound by 'let cont'.  A continuation with no
-/// parameter (or body) is used to represent a function's return continuation.
+/// Continuations are normally bound by 'let cont'.  A continuation with one
+/// parameter and no body is used to represent a function's return continuation.
 /// The return continuation is bound by the Function, not by 'let cont'.
 class Continuation extends Definition implements NodeWithBody {
   final List<Parameter> parameters;
@@ -506,7 +506,9 @@ class Continuation extends Definition implements NodeWithBody {
 
   Continuation(this.parameters);
 
-  Continuation.retrn() : parameters = null;
+  Continuation.retrn() : parameters = new List<Parameter>(1) {

[Kevin Millikin (Google), 2014/08/08 08:44:53]

= <Parameter>[new Parameter(null)] {}

[jgruber1, 2014/08/08 09:04:02]

Done.

+    parameters[0] = new Parameter(null);
+  }
 
   accept(Visitor visitor) => visitor.visitContinuation(this);
 }