Invoke the GC prolog and epilog callbacks during new gen GC too.

runtime/vm/heap.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/heap.h"
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/flags.h"
 #include "vm/isolate.h"
@@ skipping 245 matching lines @@
     class_table->ResetCountersOld();
   }
 }
 
 
 void Heap::CollectGarbage(Space space) {
   if (space == kOld) {
     CollectGarbage(space, kInvokeApiCallbacks, kOldSpace);
   } else {
     ASSERT(space == kNew);
-    CollectGarbage(space, kIgnoreApiCallbacks, kNewSpace);
+    CollectGarbage(space, kInvokeApiCallbacks, kNewSpace);
   }
 }
 
 
 void Heap::CollectAllGarbage() {
   Isolate* isolate = Isolate::Current();
   TIMERSCOPE(isolate, time_gc);
   {
     VMTagScope tagScope(isolate, VMTag::kGCNewSpaceTagId);
     RecordBeforeGC(kNew, kFull);
@@ skipping 304 matching lines @@
     heap->DisableGrowthControl();
 }
 
 
 NoHeapGrowthControlScope::~NoHeapGrowthControlScope() {
     Heap* heap = reinterpret_cast<Isolate*>(isolate())->heap();
     heap->SetGrowthControlState(current_growth_controller_state_);
 }
 
 }  // namespace dart