Add assert-in-initializer-list to formal specification.

tests/language/assertion_initializer_const_error2_test.dart

+// Copyright (c) 201, 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=--assert_initializer
+//
+// Dart test program testing assert statements.
+
+import "package:expect/expect.dart";
+
+class C {
+  final int x;
+  // Const constructors.
+  const C.cc01(this.x, y)
+      : assert(x < y)  //# cc01: compile-time error
+  ;
+  const C.cc02(x, y) : x = x,
+      assert(x < y)  //# cc02: compile-time error
+      ;
+  const C.cc03(x, y) :
+      assert(x < y),  //# cc03: compile-time error
+      x = x;
+  const C.cc04(this.x, y) : super()
+      , assert(x < y)  //# cc04: compile-time error
+      ;
+  const C.cc05(this.x, y) :
+      assert(x < y),   //# cc05: compile-time error
+      super();
+  const C.cc06(x, y) : x = x, super()
+      , assert(x < y)  //# cc06: compile-time error
+      ;
+  const C.cc07(x, y) :
+      assert(x < y),  //# cc07: compile-time error
+      super(), x = x;
+  const C.cc08(x, y) :
+      assert(x < y),  //# cc08: compile-time error
+      super(), x = x
+      , assert(y > x)  //# cc08: continued
+      ;
+  const C.cc09(this.x, y)
+      : assert(x < y, "$x < $y")  //# cc09: compile-time error
+      ;
+  const C.cc10(this.x, y)
+      : assert(x < y,)  //# cc10: compile-time error
+      ;
+  const C.cc11(this.x, y)
+      : assert(x < y, "$x < $y",)  //# cc11: compile-time error
+      ;
+}
+
+
+main() {
+  // Failing assertions in const invociations are compile-time errors.
+  const C.cc01(2, 1);  //# cc01: compile-time error
+  const C.cc02(2, 1);  //# cc02: compile-time error
+  const C.cc03(2, 1);  //# cc03: compile-time error
+  const C.cc04(2, 1);  //# cc04: compile-time error
+  const C.cc05(2, 1);  //# cc05: compile-time error
+  const C.cc06(2, 1);  //# cc06: compile-time error
+  const C.cc07(2, 1);  //# cc07: compile-time error
+  const C.cc08(2, 1);  //# cc08: compile-time error
+  const C.cc09(2, 1);  //# cc09: compile-time error
+  const C.cc10(2, 1);  //# cc10: compile-time error
+  const C.cc11(2, 1);  //# cc11: compile-time error
+}