dart2js cps: Fix a couple of minor issues.

pkg/compiler/lib/src/cps_ir/type_propagation.dart

Index: pkg/compiler/lib/src/cps_ir/type_propagation.dart
diff --git a/pkg/compiler/lib/src/cps_ir/type_propagation.dart b/pkg/compiler/lib/src/cps_ir/type_propagation.dart
index a8a7ee2e6ed8a1411c9d120765fa2318db6d07b0..186c219e7cdcb599dab1e1d0d9f58daee5f65733 100644
--- a/pkg/compiler/lib/src/cps_ir/type_propagation.dart
+++ b/pkg/compiler/lib/src/cps_ir/type_propagation.dart
@@ -502,6 +502,7 @@ class TransformingVisitor extends RecursiveVisitor {
     InvokeContinuation invoke =
         new InvokeContinuation(continuation, <Primitive>[primitive]);
     letPrim.body = invoke;
+    values[primitive] = values[continuation.parameters.single];
     primitive.hint = continuation.parameters.single.hint;
 
     return letPrim;
@@ -566,7 +567,6 @@ class TransformingVisitor extends RecursiveVisitor {
   /// True if all uses of [prim] only use its value after boolean conversion.
   bool isAlwaysBoolified(Primitive prim) {
     for (Reference ref = prim.firstRef; ref != null; ref = ref.next) {
-      Node use = ref.parent;
       if (!isBoolifyingUse(ref)) return false;
     }
     return true;