Perform RegisterReservationsForBlackAllocation atomically with deserialization of code.

src/snapshot/deserializer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/snapshot/deserializer.h"
 
 #include "src/bootstrapper.h"
 #include "src/external-reference-table.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
@@ skipping 139 matching lines @@
     deserializing_user_code_ = true;
     HandleScope scope(isolate);
     Handle<SharedFunctionInfo> result;
     {
       DisallowHeapAllocation no_gc;
       Object* root;
       VisitPointer(&root);
       DeserializeDeferredObjects();
       FlushICacheForNewCodeObjects();
       result = Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(root));
+      isolate->heap()->RegisterReservationsForBlackAllocation(reservations_);
     }
     CommitPostProcessedObjects(isolate);
-    isolate->heap()->RegisterReservationsForBlackAllocation(reservations_);
     return scope.CloseAndEscape(result);
   }
 }
 
 Deserializer::~Deserializer() {
   // TODO(svenpanne) Re-enable this assertion when v8 initialization is fixed.
   // DCHECK(source_.AtEOF());
   attached_objects_.Dispose();
 }
 
@@ skipping 639 matching lines @@
 
       default:
         CHECK(false);
     }
   }
   CHECK_EQ(limit, current);
   return true;
 }
 }  // namespace internal
 }  // namespace v8