Better stack trace support

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart

 // Copyright (c) 2015, 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.
 part of dart._runtime;
 
 bool _trapRuntimeErrors = true;
 bool _ignoreWhitelistedErrors = true;
 bool _failForWeakModeIsChecks = true;
 
 // Override, e.g., for testing
@@ skipping 70 matching lines @@
 throwAssertionError([message]) => JS(
     '',
     '''(() => {
   if ($_trapRuntimeErrors) debugger;
   let error = $message != null
         ? new $AssertionErrorWithMessage($message())
         : new $AssertionError();
   $throw_(error);
 })()''');
 
+throwCyclicInitializationError([message]) => JS(

[Jennifer Messerly, 2017/05/05 23:59:15]

I know this is the style of all these helpers but ... fyi ... I think this could
be written simply as:


throwCyclicInitializationError([String message]) {
  if (_trapRuntimeErrors) JS('', 'debugger');
  throw new CyclicInitializationError(message);
}


... only thing to watch out for in these is to avoid implicit casts for the most
part.

[vsm, 2017/05/08 17:07:44]

Done.

+    '',
+    '''(() => {
+  if ($_trapRuntimeErrors) debugger;
+  $throw_(new $CyclicInitializationError($message));
+})()''');
+
 throwNullValueError() => JS(
     '',
     '''(() => {
   // TODO(vsm): Per spec, we should throw an NSM here.  Technically, we ought
   // to thread through method info, but that uglifies the code and can't
   // actually be queried ... it only affects how the error is printed.
   if ($_trapRuntimeErrors) debugger;
   $throw_(new $NoSuchMethodError(null,
       new $Symbol('<Unexpected Null Value>'), null, null, null));
 })()''');
 
 throwNoSuchMethodError(
         receiver, memberName, positionalArguments, namedArguments) =>
     JS(
         '',
         '''(() => {
   if ($_trapRuntimeErrors) debugger;
   $throw_(new $NoSuchMethodError($receiver, $memberName, $positionalArguments, $namedArguments));
 })()''');