Observatory:

runtime/observatory/lib/src/elements/native_memory_profiler.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.
 
 library native_memory_profile;
 
 import 'dart:async';
 import 'dart:html';
 import 'package:observatory/models.dart' as M;
 import 'package:observatory/src/elements/cpu_profile/virtual_tree.dart';
@@ skipping 34 matching lines @@
   Stream<M.SampleProfileLoadingProgressEvent> _progressStream;
   M.SampleProfileLoadingProgress _progress;
   M.SampleProfileTag _tag = M.SampleProfileTag.none;
   ProfileTreeMode _mode = ProfileTreeMode.function;
   M.ProfileTreeDirection _direction = M.ProfileTreeDirection.exclusive;
   String _filter = '';
 
   M.NotificationRepository get notifications => _notifications;
   M.NativeMemorySampleProfileRepository get profiles => _profiles;
   // With non-isolate version.
-  M.VMRef get vm => _vm;
+  M.VM get vm => _vm;

[devoncarew, 2017/06/01 21:12:20]

Is this overriding something, or providing access to code outside this library?
The getter's now ~the same as the _vm field.

(from a quick pass, it looks like neither; consider just removing the getter)

[rmacnak, 2017/06/01 21:25:56]

I don't see other users, so removed. We can always add it back later if needed.

 
   factory NativeMemoryProfileElement(
       M.VM vm,
       M.EventRepository events,
       M.NotificationRepository notifications,
       M.NativeMemorySampleProfileRepository profiles,
       {RenderingQueue queue}) {
     assert(vm != null);
     assert(events != null);
     assert(notifications != null);
@@ skipping 70 matching lines @@
           }),
         new BRElement(),
         tree = new CpuProfileVirtualTreeElement(_vm, _progress.profile,
             queue: _r.queue, type: M.SampleProfileType.memory)
       ]);
     }
     children = content;
   }
 
   Future _request({bool forceFetch: false}) async {
-    for (Isolate isolate in vm.isolates) {
-      await isolate.invokeRpc("_collectAllGarbage", {});
+    for (M.Isolate isolate in vm.isolates) {
+      await isolate.collectAllGarbage();
     }
     _progress = null;
     _progressStream = _profiles.get(_vm, _tag, forceFetch: forceFetch);
     _r.dirty();
     _progress = (await _progressStream.first).progress;
     _r.dirty();
     if (M.isSampleProcessRunning(_progress.status)) {
       _progress = (await _progressStream.last).progress;
       _r.dirty();
     }
   }
 
   Future _refresh(e) async {
     e.element.disabled = true;
     await _request(forceFetch: true);
     e.element.disabled = false;
   }
 }