Use tokenPos instead of line/col in the vm service.

runtime/bin/vmservice/client/lib/src/service/object.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.
 
 part of service;
 
 /// A [ServiceObject] is an object known to the VM service and is tied
 /// to an owning [Isolate].
 abstract class ServiceObject extends Observable {
   /// The owner of this [ServiceObject].  This can be an [Isolate], a
@@ skipping 81 matching lines @@
   /// If [this] was created from a reference, load the full object
   /// from the service by calling [reload]. Else, return [this].
   Future<ServiceObject> load() {
     if (loaded) {
       return new Future.value(this);
     }
     // Call reload which will fill in the entire object.
     return reload();
   }
 
+  Future<ServiceObject> _inProgressReload;
+
   /// Reload [this]. Returns a future which completes to [this] or
   /// a [ServiceError].
   Future<ServiceObject> reload() {
     if (id == '') {
       // Errors don't have ids.
       assert(serviceType == 'Error');
       return new Future.value(this);
     }
     if (loaded && immutable) {
       return new Future.value(this);
     }
-    return vm.getAsMap(link).then((ObservableMap map) {
-        var mapType = _stripRef(map['type']);
-        if (mapType != _serviceType) {
-          // If the type changes, return a new object instead of
-          // updating the existing one.
-          assert(mapType == 'Error' || mapType == 'Null');
-          return new ServiceObject._fromMap(owner, map);
-        }
-        update(map);
-        return this;
+    if (_inProgressReload == null) {
+      _inProgressReload =  vm.getAsMap(link).then((ObservableMap map) {
+          var mapType = _stripRef(map['type']);
+          if (mapType != _serviceType) {
+            // If the type changes, return a new object instead of
+            // updating the existing one.
+            assert(mapType == 'Error' || mapType == 'Null');
+            return new ServiceObject._fromMap(owner, map);
+          }
+          update(map);
+          return this;
+      }).whenComplete(() {
+          // This reload is complete.
+          _inProgressReload = null;
       });
+    }
+    return _inProgressReload;
   }
 
   /// Update [this] using [map] as a source. [map] can be a reference.
   void update(ObservableMap map) {
     assert(_isServiceMap(map));
 
     // Don't allow the type to change on an object update.
     // TODO(turnidge): Make this a ServiceError?
     var mapIsRef = _hasRef(map['type']);
     var mapType = _stripRef(map['type']);
@@ skipping 678 matching lines @@
   @observable String kind;
 
   bool get canCache => true;
   bool get immutable => true;
 
   String _shortUrl;
   String _url;
 
   Script._empty(ServiceObjectOwner owner) : super._empty(owner);
 
+  /// This function maps a token position to a line number.
+  int tokenToLine(int token) => _tokenToLine[token];
+  Map _tokenToLine;
+
+  /// This function maps a token position to a column number.
+  int tokenToCol(int token) => _tokenToCol[token];
+  Map _tokenToCol;
+
   void _update(ObservableMap map, bool mapIsRef) {
     kind = map['kind'];
     _url = map['name'];
     _shortUrl = _url.substring(_url.lastIndexOf('/') + 1);
     name = _shortUrl;
     vmName = _url;
     _processSource(map['source']);
+    _parseTokenPosTable(map['tokenPosTable']);
+  }
+
+  void _parseTokenPosTable(List<List<int>> table) {
+    if (table == null) {
+      return;
+    }
+    _tokenToLine = {};
+    _tokenToCol = {};
+    for (var line in table) {
+      // Each entry begins with a line number...
+      var lineNumber = line[0];
+      for (var pos = 1; pos < line.length; pos += 2) {
+        // ...and is followed by (token offset, col number) pairs.
+        var tokenOffset = line[pos];
+        var colNumber = line[pos+1];
+        _tokenToLine[tokenOffset] = lineNumber;
+        _tokenToCol[tokenOffset] = colNumber;
+      }
+    }
   }
 
   void _processHits(List scriptHits) {
     if (!_loaded) {
       // Eagerly grab script source.
       load();
     }
     // Update hits table.
     for (var i = 0; i < scriptHits.length; i += 2) {
       var line = scriptHits[i];
@@ skipping 333 matching lines @@
     var v = list[i];
     if ((v is ObservableMap) && _isServiceMap(v)) {
       list[i] = owner.getFromMap(v);
     } else if (v is ObservableList) {
       _upgradeObservableList(v, owner);
     } else if (v is ObservableMap) {
       _upgradeObservableMap(v, owner);
     }
   }
 }