Fetch global object from jsproxy prototype instead of embedding it in StoreGlobal.

src/code-stubs.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_CODE_STUBS_H_
 #define V8_CODE_STUBS_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 1074 matching lines @@
   }
 
   static Handle<HeapObject> global_placeholder(Isolate* isolate) {
     return isolate->factory()->uninitialized_value();
   }
 
   Handle<Code> GetCodeCopyFromTemplate(Handle<GlobalObject> global,
                                        Handle<PropertyCell> cell) {
     if (check_global()) {
       Code::FindAndReplacePattern pattern;
-      pattern.Add(Handle<Map>(global_placeholder(isolate())->map()), global);
-      pattern.Add(isolate()->factory()->meta_map(), Handle<Map>(global->map()));
+      pattern.Add(isolate()->factory()->meta_map(),
+                  Map::WeakCellForMap(Handle<Map>(global->map())));
       pattern.Add(isolate()->factory()->global_property_cell_map(), cell);
       return CodeStub::GetCodeCopy(pattern);
     } else {
       Code::FindAndReplacePattern pattern;
       pattern.Add(isolate()->factory()->global_property_cell_map(), cell);
       return CodeStub::GetCodeCopy(pattern);
     }
   }
 
   Code::Kind kind() const OVERRIDE { return Code::STORE_IC; }
@@ skipping 1564 matching lines @@
 
 #undef DEFINE_CALL_INTERFACE_DESCRIPTOR
 #undef DEFINE_PLATFORM_CODE_STUB
 #undef DEFINE_HANDLER_CODE_STUB
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_