Update isolate documentation.

sdk/lib/isolate/isolate.dart

Index: sdk/lib/isolate/isolate.dart
diff --git a/sdk/lib/isolate/isolate.dart b/sdk/lib/isolate/isolate.dart
index efc6ca252557a46969ddb6a3131c175ec2f29080..15ae1792e232346c07fdc54f3ccb2ea1d6a76229 100644
--- a/sdk/lib/isolate/isolate.dart
+++ b/sdk/lib/isolate/isolate.dart
@@ -26,6 +26,18 @@ class IsolateSpawnException implements Exception {
   final String _s;
 }
 
+/**
+ * Thrown when an isolate message is invalid.
+ */
+class IsolateMessageException implements Exception {
+  final String _message;
+
+  // TODO(floitsch): give access to the message that couldn't be sent.

[Lasse Reichstein Nielsen, 2013/12/11 10:38:28]

Ah, agree :)

+  const IsolateMessageException(String this._message);
+
+  String toString() => "IsolateMessageException: '$_message'";
+}
+
 class Isolate {
 
   final SendPort _controlPort;
@@ -50,6 +62,8 @@ class Isolate {
    *
    * Returns a future that will complete with an [Isolate] instance if the
    * spawning succeeded. It will complete with an error otherwise.
+   *
+   * All errors are reported asynchronously through the returned future.

[Lasse Reichstein Nielsen, 2013/12/11 10:38:28]

Not necessarily all errors.
Let's specify which arguments and conditions can cause an exception, and that
these exceptions are returned through the future.

[floitsch, 2013/12/11 12:14:16]

Yes.
This should be changed to list all the possible exceptions and to make sure that
they are dealt with correctly.

    */
   external static Future<Isolate> spawn(void entryPoint(message), var message);
 
@@ -71,6 +85,8 @@ class Isolate {
    *
    * Returns a future that will complete with an [Isolate] instance if the
    * spawning succeeded. It will complete with an error otherwise.
+   *
+   * All errors are reported asynchronously through the returned future.

[Lasse Reichstein Nielsen, 2013/12/11 10:38:28]

Ditto.

    */
   external static Future<Isolate> spawnUri(
       Uri uri, List<String> args, var message);