Change how we deal with manual inlining of argument error and NSM when propagating types. This chan…

tests/compiler/dart2js/is_inference_test.dart

Index: tests/compiler/dart2js/is_inference_test.dart
===================================================================
--- tests/compiler/dart2js/is_inference_test.dart	(revision 24017)
+++ tests/compiler/dart2js/is_inference_test.dart	(working copy)
@@ -7,6 +7,7 @@
 
 const String TEST_IF = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is int) {
     param = param + 42;
   }
@@ -16,6 +17,7 @@
 
 const String TEST_IF_ELSE = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is int) {
     param = param + 42;
   } else {
@@ -27,6 +29,7 @@
 
 const String TEST_IF_RETURN = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is int) {
     return param + 42;
   }
@@ -36,6 +39,7 @@
 
 const String TEST_IF_NOT_ELSE = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is !int) {
     param = param + 53;
   } else {
@@ -47,6 +51,7 @@
 
 const String TEST_IF_NOT_RETURN = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is !int) return param + 53;
   return param + 42;
 }
@@ -54,6 +59,7 @@
 
 const String TEST_IF_NOT_ELSE_RETURN = r"""
 test(param) {
+  print('Printing this ensures that String+ is in the system.');
   if (param is !int) {
     return param + 53;
   } else {