Implement 'print', 'up', 'down', and 'frame' commands in the Observatory debugger.

runtime/observatory/lib/service_common.dart

 // Copyright (c) 2014, 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 service_common;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:typed_data';
 
@@ skipping 185 matching lines @@
       // from the vm.
       postServiceEvent(response, null);
       return;
     }
     // Complete request.
     var request = _pendingRequests.remove(serial);
     if (request == null) {
       Logger.root.severe('Received unexpected message: ${map}');
       return;
     }
+    if (request.method != 'getTagProfile' &&
+        request.method != 'getIsolateMetric' &&
+        request.method != 'getVMMetric') {
+      Logger.root.info(
+          'RESPONSE [${serial}] ${request.method}');
+    }
     request.completer.complete(response);
   }
 
   // WebSocket message event handler.
   void _onMessage(dynamic data) {
     if (data is! String) {
       _onBinaryMessage(data);
     } else {
       _onStringMessage(data);
     }
@@ skipping 37 matching lines @@
     Logger.root.info('Sending all delayed requests.');
     // Send all delayed requests.
     _delayedRequests.forEach(_sendRequest);
     // Clear all delayed requests.
     _delayedRequests.clear();
   }
 
   /// Send the request over WebSocket.
   void _sendRequest(String serial, _WebSocketRequest request) {
     assert (_webSocket.isOpen);
-    if (request.method != 'getTagProfile' &&
-        request.method != 'getIsolateMetric' &&
-        request.method != 'getVMMetric') {
-      Logger.root.info('GET ${request.method} from ${target.networkAddress}');
-    }
     // Mark request as pending.
     assert(_pendingRequests.containsKey(serial) == false);
     _pendingRequests[serial] = request;
     var message;
     // Encode message.
     if (target.chrome) {
       message = JSON.encode({
         'id': int.parse(serial),
         'method': 'Dart.observatoryQuery',
         'params': {
           'id': serial,
           'query': request.method
         }
       });
     } else {
       message = JSON.encode({'id': serial,
                              'method': request.method,
                              'params': request.params});
     }
+    if (request.method != 'getTagProfile' &&
+        request.method != 'getIsolateMetric' &&
+        request.method != 'getVMMetric') {
+      Logger.root.info(
+          'GET [${serial}] ${request.method} from ${target.networkAddress}');
+    }
     // Send message.
     _webSocket.send(message);
   }
 }