Remove deprecated parts of dart:async.

tests/standalone/io/http_content_length_test.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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import "package:expect/expect.dart";
@@ skipping 24 matching lines @@
           // reports an error.
           response.write("x");
           // Subsequent write are ignored as there is already an
           // error.
           response.write("x");
           // After an explicit close, write becomes a state error
           // because we have said we will not add more.
           response.close();
           response.write("x");
         },
-        onError: (e) {
+        onError: (e, trace) {
           String msg = "Unexpected server error $e";
-          var trace = getAttachedStackTrace(e);
           if (trace != null) msg += "\nStackTrace: $trace";
           Expect.fail(msg);
         });
 
     HttpClient client = new HttpClient();
     for (int i = 0; i < totalConnections; i++) {
       client.get("127.0.0.1", server.port, "/")
           .then((request) {
             if (explicitContentLength) {
               request.contentLength = 0;
             }
             return request.close();
           })
           .then((response) {
             Expect.equals("0", response.headers.value('content-length'));
             Expect.equals(0, response.contentLength);
             response.drain();
           })
-          .catchError((e) {
+          .catchError((e, trace) {
             String msg = "Unexpected error $e";
-            var trace = getAttachedStackTrace(e);
             if (trace != null) msg += "\nStackTrace: $trace";
             Expect.fail(msg);
          });
     }
   });
 }
 
 void testBody(int totalConnections, bool useHeader) {
   HttpServer.bind("127.0.0.1", 0, backlog: totalConnections).then((server) {
     int serverCount = 0;
@@ skipping 22 matching lines @@
                     .catchError((error) {
                       Expect.isTrue(error is HttpException, "[$error]");
                       if (++serverCount == totalConnections) {
                         server.close();
                       }
                     });
                 response.close();
                 response.write("x");
               });
         },
-        onError: (e) {
+        onError: (e, trace) {
           String msg = "Unexpected error $e";
-          var trace = getAttachedStackTrace(e);
           if (trace != null) msg += "\nStackTrace: $trace";
           Expect.fail(msg);
         });
 
     int clientCount = 0;
     HttpClient client = new HttpClient();
     for (int i = 0; i < totalConnections; i++) {
       client.get("127.0.0.1", server.port, "/")
           .then((request) {
             if (useHeader) {
@@ skipping 11 matching lines @@
           .then((response) {
             Expect.equals("2", response.headers.value('content-length'));
             Expect.equals(2, response.contentLength);
             response.listen(
                 (d) {},
                 onDone: () {
                   if (++clientCount == totalConnections) {
                     client.close();
                   }
                 },
-                onError: (error) {
+                onError: (error, trace) {
                   // Undefined what server response sends.
                 });
           });
     }
   });
 }
 
 void testBodyChunked(int totalConnections, bool useHeader) {
   HttpServer.bind("127.0.0.1", 0, backlog: totalConnections).then((server) {
     server.listen(
@@ skipping 14 matching lines @@
                 response.write("x");
                 Expect.throws(
                     () => response.headers.chunkedTransferEncoding = false,
                     (e) => e is HttpException);
                 response.write("x");
                 response.write("x");
                 response.close();
                 response.write("x");
               });
         },
-        onError: (e) {
+        onError: (e, trace) {
           String msg = "Unexpected error $e";
-          var trace = getAttachedStackTrace(e);
           if (trace != null) msg += "\nStackTrace: $trace";
           Expect.fail(msg);
         });
 
     int count = 0;
     HttpClient client = new HttpClient();
     for (int i = 0; i < totalConnections; i++) {
       client.get("127.0.0.1", server.port, "/")
           .then((request) {
             if (useHeader) {
@@ skipping 15 matching lines @@
             Expect.equals(-1, response.contentLength);
             response.listen(
                 (d) {},
                 onDone: () {
                   if (++count == totalConnections) {
                     client.close();
                     server.close();
                   }
                 });
           })
-          .catchError((e) {
+          .catchError((e, trace) {
             String msg = "Unexpected error $e";
-            var trace = getAttachedStackTrace(e);
             if (trace != null) msg += "\nStackTrace: $trace";
             Expect.fail(msg);
           });
     }
   });
 }
 
 void testSetContentLength() {
   HttpServer.bind("127.0.0.1", 0).then((server) {
     server.listen(
@@ skipping 26 matching lines @@
   testNoBody(5, false);
   testNoBody(25, false);
   testNoBody(5, true);
   testNoBody(25, true);
   testBody(5, false);
   testBody(5, true);
   testBodyChunked(5, false);
   testBodyChunked(5, true);
   testSetContentLength();
 }