Implement growth policy for old space using time and space signals.

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 84 matching lines @@
       OS::Print("Size of isolate snapshot = %ld\n", snapshot->length());
     }
     SnapshotReader reader(snapshot, isolate);
     reader.ReadFullSnapshot();
     if (FLAG_trace_isolates) {
       isolate->heap()->PrintSizes();
     }
   }
 
   StubCode::Init(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();
   isolate->Shutdown();
   delete isolate;
 }
 
 }  // namespace dart