Revert "Make Error capture a stacktrace when it is created."

sdk/lib/core/errors.dart

 // Copyright (c) 2012, 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.core;
 
 class Error {
-  final StackTrace stackTrace;
-
-  Error() : stackTrace = ((){ try { throw 0; } catch (e, s) { return s; } })();
+  const Error();
 
   /**
    * Safely convert a value to a [String] description.
    *
    * The conversion is guaranteed to not throw, so it won't use the object's
    * toString method.
    */
   static String safeToString(Object object) {
     if (object is int || object is double || object is bool || null == object) {
       return object.toString();
@@ skipping 12 matching lines @@
     return _objectToString(object);
   }
 
   external static String _objectToString(Object object);
 }
 
 /**
  * Error thrown by the runtime system when an assert statement fails.
  */
 class AssertionError implements Error {
-  /** Assertion errors don't capture stack traces. */
-  StackTrace get stackTrace => null;
 }
 
 /**
  * Error thrown by the runtime system when a type assertion fails.
  */
 class TypeError implements AssertionError {
-  /** Type errors don't capture stack traces. */
-  StackTrace get stackTrace => null;
 }
 
 /**
  * Error thrown by the runtime system when a cast operation fails.
  */
 class CastError implements Error {
-  /** Cast errors don't capture stack traces. */
-  StackTrace get stackTrace => null;
 }
 
 /**
  * Error thrown when attempting to throw [:null:].
  */
 class NullThrownError implements Error {
   const NullThrownError();
-  /** NullThrown errors don't capture stack traces. */
-  StackTrace get stackTrace => null;
   String toString() => "Throw of null.";
 }
 
 /**
  * Error thrown when a function is passed an unacceptable argument.
  */
-class ArgumentError extends Error {
+class ArgumentError implements Error {
   final message;
 
   /** The [message] describes the erroneous argument. */
   ArgumentError([this.message]);
 
   String toString() {
     if (message != null) {
       return "Illegal argument(s): $message";
     }
     return "Illegal argument(s)";
@@ skipping 28 matching lines @@
 /**
  * Error thrown when control reaches the end of a switch case.
  *
  * The Dart specification requires this error to be thrown when
  * control reaches the end of a switch case (except the last case
  * of a switch) without meeting a break or similar end of the control
  * flow.
  */
 class FallThroughError implements Error {
   const FallThroughError();
-  StackTrace get stackTrace => null;
 }
 
-// TODO(lrn): Class description. Ensure that this is the class thrown by
-// both implementations, or move it to the one that uses it.
+
 class AbstractClassInstantiationError implements Error {
   final String _className;
   const AbstractClassInstantiationError(String this._className);
-  StackTrace get stackTrace => null;
   String toString() => "Cannot instantiate abstract class: '$_className'";
 }
 
-
 /**
  * Error thrown by the default implementation of [:noSuchMethod:] on [Object].
  */
 class NoSuchMethodError implements Error {
   final Object _receiver;
   final String _memberName;
   final List _arguments;
   final Map<String,dynamic> _namedArguments;
   final List _existingArgumentNames;
 
   /**
    * Create a [NoSuchMethodError] corresponding to a failed method call.
    *
    * The first parameter to this constructor is the receiver of the method call.
    * That is, the object on which the method was attempted called.
    * The second parameter is the name of the called method or accessor.
    * The third parameter is a list of the positional arguments that the method
    * was called with.
    * The fourth parameter is a map from [String] names to the values of named
    * arguments that the method was called with.
    * The optional [exisitingArgumentNames] is the expected parameters of a
    * method with the same name on the receiver, if available. This is
    * the method that would have been called if the parameters had matched.
    */
-  NoSuchMethodError(Object this._receiver,
+  const NoSuchMethodError(Object this._receiver,
                           String this._memberName,
                           List this._arguments,
                           Map<String,dynamic> this._namedArguments,
                           [List existingArgumentNames = null])
       : this._existingArgumentNames = existingArgumentNames;
 
-  StackTrace get stackTrace => null;
-
   external String toString();
 }
 
 
 /**
  * The operation was not allowed by the object.
  *
  * This [Error] is thrown when an instance cannot implement one of the methods
  * in its signature.
  */
-class UnsupportedError extends Error {
+class UnsupportedError implements Error {
   final String message;
   UnsupportedError(this.message);
   String toString() => "Unsupported operation: $message";
 }
 
 
 /**
  * Thrown by operations that have not been implemented yet.
  *
  * This [Error] is thrown by unfinished code that hasn't yet implemented
  * all the features it needs.
  *
  * If a class is not intending to implement the feature, it should throw
  * an [UnsupportedError] instead. This error is only intended for
  * use during development.
  */
-class UnimplementedError extends UnsupportedError {
-  UnimplementedError([String message]) : super(message);
+class UnimplementedError implements UnsupportedError {
+  final String message;
+  UnimplementedError([String this.message]);
   String toString() => (this.message != null
                         ? "UnimplementedError: $message"
                         : "UnimplementedError");
 }
 
 
 /**
  * The operation was not allowed by the current state of the object.
  *
  * This is a generic error used for a variety of different erroneous
  * actions. The message should be descriptive.
  */
-class StateError extends Error {
+class StateError implements Error {
   final String message;
   StateError(this.message);
   String toString() => "Bad state: $message";
 }
 
 
 /**
  * Error occurring when a collection is modified during iteration.
  *
  * Some modifications may be allowed for some collections, so each collection
  * ([Iterable] or similar collection of values) should declare which operations
  * are allowed during an iteration.
  */
-class ConcurrentModificationError extends Error {
+class ConcurrentModificationError implements Error {
   /** The object that was modified in an incompatible way. */
   final Object modifiedObject;
 
-  ConcurrentModificationError([this.modifiedObject]);
+  const ConcurrentModificationError([this.modifiedObject]);
 
   String toString() {
     if (modifiedObject == null) {
       return "Concurrent modification during iteration.";
     }
     return "Concurrent modification during iteration: "
            "${Error.safeToString(modifiedObject)}.";
   }
 }
 
 
 class OutOfMemoryError implements Error {
   const OutOfMemoryError();
-  StackTrace get stackTrace => null;
   String toString() => "Out of Memory";
 }
 
 
 class StackOverflowError implements Error {
   const StackOverflowError();
-  StackTrace get stackTrace => null;
   String toString() => "Stack Overflow";
 }
 
 /**
  * Error thrown when a lazily initialized variable cannot be initialized.
  *
  * A static/library variable with an initializer expression is initialized
  * the first time it is read. If evaluating the initializer expression causes
  * another read of the variable, this error is thrown.
  */
 class CyclicInitializationError implements Error {
   final String variableName;
   const CyclicInitializationError([this.variableName]);
-  StackTrace get stackTrace => null;
   String toString() => variableName == null
       ? "Reading static variable during its initialization"
       : "Reading static variable '$variableName' during its initialization";
 }