Add optional max elements limit for Map/Set mirror iterator preview.

src/runtime/runtime.h

 // Copyright 2012 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.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/zone.h"
@@ skipping 315 matching lines @@
   F(MapIteratorClone, 1, 1)                            \
   F(MapIteratorNext, 2, 1)                             \
                                                        \
   /* Harmony weak maps and sets */                     \
   F(WeakCollectionInitialize, 1, 1)                    \
   F(WeakCollectionGet, 2, 1)                           \
   F(WeakCollectionHas, 2, 1)                           \
   F(WeakCollectionDelete, 2, 1)                        \
   F(WeakCollectionSet, 3, 1)                           \
                                                        \
-  F(GetWeakMapEntries, 1, 1)                           \
-  F(GetWeakSetValues, 1, 1)                            \
+  F(GetWeakMapEntries, 2, 1)                           \
+  F(GetWeakSetValues, 2, 1)                            \
                                                        \
   /* Harmony events */                                 \
   F(EnqueueMicrotask, 1, 1)                            \
   F(RunMicrotasks, 0, 1)                               \
                                                        \
   /* Harmony observe */                                \
   F(IsObserved, 1, 1)                                  \
   F(SetIsObserved, 1, 1)                               \
   F(GetObservationState, 0, 1)                         \
   F(ObservationWeakMapCreate, 0, 1)                    \
@@ skipping 536 matching lines @@
 class AllocateTargetSpace : public BitField<AllocationSpace, 1, 3> {};
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 class DeclareGlobalsStrictMode : public BitField<StrictMode, 2, 1> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_