Make several service protocol RPCs private.

runtime/observatory/lib/src/elements/heap_map.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 heap_map_element;
 
 import 'dart:async';
 import 'dart:html';
 import 'dart:math';
 import 'observatory_element.dart';
@@ skipping 206 matching lines @@
     new Future(() {
       _renderPages(startPage + 1);
     });
   }
 
   void isolateChanged(oldValue) {
     if (isolate == null) {
       fragmentation = null;
       return;
     }
-    isolate.invokeRpc('getHeapMap', {}).then((ServiceMap response) {
+    isolate.invokeRpc('_getHeapMap', {}).then((ServiceMap response) {
       assert(response['type'] == 'HeapMap');
       fragmentation = response;
     }).catchError((e, st) {
       Logger.root.info('$e $st');
     });
   }
 
   Future refresh() {
     if (isolate == null) {
       return new Future.value(null);
     }
-    return isolate.invokeRpc('getHeapMap', {}).then((ServiceMap response) {
+    return isolate.invokeRpc('_getHeapMap', {}).then((ServiceMap response) {
       assert(response['type'] == 'HeapMap');
       fragmentation = response;
     });
   }
 
   void fragmentationChanged(oldValue) {
     // Async, in case attached has not yet run (observed in JS version).
     new Future(() {
       _updateFragmentationData();
     });
   }
 }