Track live instance and allocation counts for classes

runtime/bin/vmservice/client/lib/src/observatory/application.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.
 
 part of observatory;
 
 /// The observatory application. Instances of this are created and owned
 /// by the observatory_application custom element.
 class ObservatoryApplication extends Observable {
   @observable final LocationManager locationManager;
@@ skipping 32 matching lines @@
   }
 
   /// Return the name of the isolate with [id].
   String getIsolateName(int id) {
     var isolate = getIsolate(id);
     if (isolate == null) {
       return 'Null Isolate';
     }
     return isolate.name;
   }
+
+  static const int KB = 1024;
+  static const int MB = KB * 1024;
+  static String scaledSizeUnits(int x) {
+    if (x > 2 * MB) {
+      var y = x / MB;
+      return '${y.toStringAsFixed(1)} MB';
+    } else if (x > 2 * KB) {
+      var y = x / KB;
+      return '${y.toStringAsFixed(1)} KB';
+    }
+    var y = x.toDouble();
+    return '${y.toStringAsFixed(1)} B';
+  }
+
+  static String timeUnits(double x) {
+    return x.toStringAsFixed(4);
+  }
 }