First version of typr propagation in the new IR.

tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart

Index: tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart
diff --git a/tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart b/tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart
index 746735b13637299a4fd6fd0004a8f60cf80762d4..2695588a82560ce4dafae22a62b64594f1e16dc3 100644
--- a/tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart
+++ b/tests/compiler/dart2js/js_backend_cps_ir_control_flow.dart
@@ -116,11 +116,25 @@ main() {
   if (1) {
     print('bad');
   } else {
-    print('ok');
+    print('good');
   }
 }""","""
 function() {
-  P.print("bad");
+  P.print("good");
+  return null;
+}"""),
+  const TestEntry("""
+foo() => 2;
+main() {
+  if (foo()) {
+    print('bad');
+  } else {
+    print('good');
+  }
+}""","""
+function() {
+  V.foo();
+  P.print("good");
   return null;
 }"""),
 ];