Added ability to request zone memory information for all isolates through the VM service and added …

runtime/observatory/lib/src/models/objects/zone.dart

Index: runtime/observatory/lib/src/models/objects/zone.dart
diff --git a/runtime/observatory/lib/src/models/objects/zone.dart b/runtime/observatory/lib/src/models/objects/zone.dart
new file mode 100644
index 0000000000000000000000000000000000000000..a21328e454d20df4563a4975edac05c75337f2b3
--- /dev/null
+++ b/runtime/observatory/lib/src/models/objects/zone.dart
@@ -0,0 +1,14 @@
+// Copyright (c) 2016, 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 models;
+
+abstract class Zone {
+  /// The total amount of memory allocated in the zone, including
+  /// memory that is not actually being used.

[Cutch, 2016/12/19 14:46:09]

here and elsewhere: describe the units of memory. Are these words, bytes, megs?

[bkonyi, 2016/12/19 16:40:20]

Done.

+  int get capacity;
+
+  /// The total amount of memory actually used in the zone.
+  int get used;
+}