Fix 2172: report 'int' instead of Smi, Mint and Bigint when throwing TypeError.

tests/language/src/TypeVMTest.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // VMOptions=--enable_type_checks --enable_asserts
 //
 // Dart test program testing type checks.
 
 class TypeTest {
   static test() {
     int result = 0;
@@ skipping 342 matching lines @@
   }
 
 
   static int testFactory() {
     int result = 0;
     try {
       var x = new C();
     } catch (TypeError error) {
       result++;
       Expect.equals("C", error.dstType);
-      Expect.equals("Smi", error.srcType);
+      Expect.equals("int", error.srcType);
       Expect.equals("function result", error.dstName);
       int pos = error.url.lastIndexOf("/", error.url.length);
       if (pos == -1) {
         pos = error.url.lastIndexOf("\\", error.url.length);
       }
       String subs = error.url.substring(pos + 1, error.url.length);
       Expect.equals("TypeVMTest.dart", subs);
       Expect.equals(472, error.line);
       Expect.equals(12, error.column);
     }
@@ skipping 96 matching lines @@
 class C {
   factory C() {
     return 1;  // Implicit result type is 'C', not int.
   }
 }
 
 
 main() {
   TypeTest.testMain();
 }