Store Object.observe state per-isolate rather than per-context

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2796 matching lines @@
     if (!maybe_obj->ToObject(&obj)) return false;
   }
   set_regexp_multiple_cache(FixedArray::cast(obj));
 
   // Allocate cache for external strings pointing to native source code.
   { MaybeObject* maybe_obj = AllocateFixedArray(Natives::GetBuiltinsCount());
     if (!maybe_obj->ToObject(&obj)) return false;
   }
   set_natives_source_cache(FixedArray::cast(obj));
 
+  // Allocate object to hold object observation state.
+  Map* object_observation_map;
+  { MaybeObject* maybe_obj = AllocateMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
+    if (!maybe_obj->To(&object_observation_map)) return false;
+  }
+  { MaybeObject* maybe_obj = AllocateJSObjectFromMap(object_observation_map);
+    if (!maybe_obj->ToObject(&obj)) return false;
+  }
+  set_object_observation_state(JSObject::cast(obj));
+
   // Handling of script id generation is in FACTORY->NewScript.
   set_last_script_id(undefined_value());
 
   // Initialize keyed lookup cache.
   isolate_->keyed_lookup_cache()->Clear();
 
   // Initialize context slot cache.
   isolate_->context_slot_cache()->Clear();
 
   // Initialize descriptor cache.
@@ skipping 4533 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   memcpy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   memcpy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal