Merge the Merlin heap tracing to top-of-trunk.

runtime/vm/dart.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/dart.h"
 
 #include "vm/dart_api_state.h"
 #include "vm/flags.h"
 #include "vm/freelist.h"
 #include "vm/handles.h"
@@ skipping 151 matching lines @@
     reader.ReadFullSnapshot();
     if (FLAG_trace_isolates) {
       isolate->heap()->PrintSizes();
     }
     if (FLAG_print_bootstrap) {
       PrintLibrarySources(isolate);
     }
   }
 
   StubCode::Init(isolate);
+  if (HeapTrace::is_enabled()) {
+    isolate->heap()->trace()->InitializeIsolateTracing(isolate);
+  }
   isolate->heap()->EnableGrowthControl();
   isolate->set_init_callback_data(data);
   if (FLAG_print_class_table) {
     isolate->class_table()->Print();
   }
   return Error::null();
 }
 
 
 void Dart::ShutdownIsolate() {
   Isolate* isolate = Isolate::Current();
   if (FLAG_trace_isolates) {
     isolate->heap()->PrintSizes();
   }
   void* callback_data = isolate->init_callback_data();
   isolate->Shutdown();
   delete isolate;
 
   Dart_IsolateShutdownCallback callback = Isolate::ShutdownCallback();
   if (callback != NULL) {
     (callback)(callback_data);
   }
 }
 
 }  // namespace dart