Rewrite negative const tests into a few multi tests.

tests/language/src/ConstConstructorSyntaxTest.dart

Index: tests/language/src/ConstConstructorSyntaxTest.dart
diff --git a/tests/language/src/ConstConstructorSyntaxTest.dart b/tests/language/src/ConstConstructorSyntaxTest.dart
index 468269a5a0c2b02e8bf765b06936d14de4db0c13..ebbc33481a3173fe095cb69546444a90094641c6 100644
--- a/tests/language/src/ConstConstructorSyntaxTest.dart
+++ b/tests/language/src/ConstConstructorSyntaxTest.dart
@@ -7,6 +7,7 @@ main() {
   var i0 = const I0(); /// 02: compile-time error
   var c1 = const C1();
   var c2 = const C2(); /// 03: compile-time error
+  var c3 = const C3();
 }
 
 interface I0 default C0 {
@@ -25,3 +26,10 @@ class C1 {
 class C2 {
   C2();
 }
+
+class C3 {
+  const C3()
+      : field = new C0() /// 05: compile-time error
+  ;
+  final field = null;
+}