dart2js: put all type-test related properties on the prototype and not on the constructor.

tests/compiler/dart2js/deferred_emit_type_checks_test.dart

Index: tests/compiler/dart2js/deferred_emit_type_checks_test.dart
diff --git a/tests/compiler/dart2js/deferred_emit_type_checks_test.dart b/tests/compiler/dart2js/deferred_emit_type_checks_test.dart
index d397ababc0fb6e613034f3ea24123b1439db7d65..e236c691b4dee8c4ef91071503e3fe756b979819 100644
--- a/tests/compiler/dart2js/deferred_emit_type_checks_test.dart
+++ b/tests/compiler/dart2js/deferred_emit_type_checks_test.dart
@@ -53,11 +53,8 @@ void main() {
     String mainOutput = outputs['main.js'].mem[0];
     String deferredOutput = outputs['out_1.part.js'].mem[0];
     String isPrefix = compiler.backend.namer.operatorIsPrefix;
-    String escapedIsPrefix = isPrefix.replaceAll(r'$', r'\$');
-    RegExp re = new RegExp(r"\n  _ = .\.A;\n  _."
-                            "${escapedIsPrefix}A = TRUE;");
-    Expect.isTrue(re.hasMatch(deferredOutput));
-    Expect.isFalse(re.hasMatch(mainOutput));
+    Expect.isTrue(deferredOutput.contains('${isPrefix}A: true'));
+    Expect.isFalse(mainOutput.contains('${isPrefix}A: true'));
   }));
 }