Properly handle errors thrown in [Chain.capture]'s [onError] handler.

pkg/stack_trace/lib/src/stack_zone_specification.dart

 // Copyright (c) 2013, 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.
 
 library stack_trace.stack_zone_specification;
 
 import 'dart:async';
 
 import 'trace.dart';
 import 'chain.dart';
@@ skipping 127 matching lines @@
     var node = _createNode(1);
     return parent.registerBinaryCallback(zone, (arg1, arg2) {
       return _run(() => f(arg1, arg2), node);
     });
   }
 
   /// Looks up the chain associated with [stackTrace] and passes it either to
   /// [_onError] or [parent]'s error handler.
   handleUncaughtError(Zone self, ZoneDelegate parent, Zone zone, error,
       StackTrace stackTrace) {
+    var stackChain = chainFor(stackTrace);
     if (_onError == null) {
-      return parent.handleUncaughtError(zone, error, chainFor(stackTrace));
-    } else {
-      _onError(error, chainFor(stackTrace));
+      return parent.handleUncaughtError(zone, error, stackChain);
+    }
+
+    // TODO(nweiz): Currently this copies a lot of logic from [runZoned]. Just
+    // allow [runBinary] to throw instead once issue 18134 is fixed.
+    try {
+      return parent.runBinary(zone, _onError, error, stackChain);
+    } catch (newError, newStackTrace) {
+      if (identical(newError, error)) {
+        return parent.handleUncaughtError(zone, error, stackChain);
+      } else {
+        return parent.handleUncaughtError(zone, newError, newStackTrace);
+      }
     }
   }
 
   /// Creates a [_Node] with the current stack trace and linked to
   /// [_currentNode].
   ///
   /// By default, the first frame of the first trace will be the line where
   /// [_createNode] is called. If [level] is passed, the first trace will start
   /// that many frames up instead.
   _Node _createNode([int level=0]) =>
@@ skipping 34 matching lines @@
   Chain toChain() {
     var nodes = <Trace>[];
     var node = this;
     while (node != null) {
       nodes.add(node.trace);
       node = node.previous;
     }
     return new Chain(nodes);
   }
 }