[api] Prototype WeakRef implementation

src/heap/scavenger.cc

 // Copyright 2015 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/heap/scavenger.h"
 
 #include "src/contexts.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/incremental-marking.h"
 #include "src/heap/objects-visiting-inl.h"
@@ skipping 51 matching lines @@
             Symbol::kSize>);
 
     table_.Register(
         kVisitSharedFunctionInfo,
         &ObjectEvacuationStrategy<POINTER_OBJECT>::template VisitSpecialized<
             SharedFunctionInfo::kSize>);
 
     table_.Register(kVisitJSWeakCollection,
                     &ObjectEvacuationStrategy<POINTER_OBJECT>::Visit);
 
+    table_.Register(kVisitJSWeakRef,
+                    &ObjectEvacuationStrategy<POINTER_OBJECT>::Visit);
+
     table_.Register(kVisitJSRegExp,
                     &ObjectEvacuationStrategy<POINTER_OBJECT>::Visit);
 
     table_.Register(kVisitJSFunction, &EvacuateJSFunction);
 
     table_.Register(kVisitDataObject,
                     &ObjectEvacuationStrategy<DATA_OBJECT>::Visit);
 
     table_.Register(kVisitJSObjectFast,
                     &ObjectEvacuationStrategy<POINTER_OBJECT>::Visit);
@@ skipping 391 matching lines @@
 void ScavengeVisitor::ScavengePointer(Object** p) {
   Object* object = *p;
   if (!heap_->InNewSpace(object)) return;
 
   Scavenger::ScavengeObject(reinterpret_cast<HeapObject**>(p),
                             reinterpret_cast<HeapObject*>(object));
 }
 
 }  // namespace internal
 }  // namespace v8