Add unhandledExceptionCallback to streamSpawnFunction.

sdk/lib/isolate/isolate_stream.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.isolate;
 
 /**
  * The initial [IsolateStream] available by default for this isolate. This
  * [IsolateStream] is created automatically and it is commonly used to establish
  * the first communication between isolates (see [streamSpawnFunction] and
@@ skipping 178 matching lines @@
  * argument must be a static top-level function or a static method that takes no
  * arguments.
  *
  * When any isolate starts (even the main script of the application), a default
  * [IsolateStream] is created for it. This sink is available from the top-level
  * getter [stream] defined in this library.
  *
  * [spawnFunction] returns an [IsolateSink] feeding into the child isolate's
  * default stream.
  *
+ * The optional [unhandledExceptionCallback] argument is invoked whenever an
+ * exception inside the isolate is unhandled. It can be seen as a big
+ * `try/catch` around everything that is executed inside the isolate. The
+ * callback should return `true` when it was able to handled the exception.
+ *
  * See comments at the top of this library for more details.
  */
-IsolateSink streamSpawnFunction(void topLevelFunction()) {
-  SendPort sendPort = spawnFunction(topLevelFunction);
+IsolateSink streamSpawnFunction(
+    void topLevelFunction(),
+    [bool unhandledExceptionCallback(IsolateUnhandledException e)]) {
+  SendPort sendPort = spawnFunction(topLevelFunction,
+                                    unhandledExceptionCallback);
   return new IsolateSink._fromPort(sendPort);
 }
 
 /**
  * Creates and spawns an isolate whose code is available at [uri].  Like with
  * [streamSpawnFunction], the child isolate will have a default [IsolateStream],
  * and a this function returns an [IsolateSink] feeding into it.
  *
  * See comments at the top of this library for more details.
  */
 IsolateSink streamSpawnUri(String uri) {
   SendPort sendPort = spawnUri(uri);
   return new IsolateSink._fromPort(sendPort);
 }