Revert merges of r12531 and r12562 from 3.12 branch, going back to 3.12.19.12

src/objects.h

 // 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 1665 matching lines @@
 
   MUST_USE_RESULT MaybeObject* DefineAccessor(AccessorInfo* info);
 
   // Used from Object::GetProperty().
   MUST_USE_RESULT MaybeObject* GetPropertyWithFailedAccessCheck(
       Object* receiver,
       LookupResult* result,
       String* name,
       PropertyAttributes* attributes);
   MUST_USE_RESULT MaybeObject* GetPropertyWithInterceptor(
-      Object* receiver,
+      JSReceiver* receiver,
       String* name,
       PropertyAttributes* attributes);
   MUST_USE_RESULT MaybeObject* GetPropertyPostInterceptor(
-      Object* receiver,
+      JSReceiver* receiver,
       String* name,
       PropertyAttributes* attributes);
   MUST_USE_RESULT MaybeObject* GetLocalPropertyPostInterceptor(
-      Object* receiver,
+      JSReceiver* receiver,
       String* name,
       PropertyAttributes* attributes);
 
   // Returns true if this is an instance of an api function and has
   // been modified since it was created.  May give false positives.
   bool IsDirty();
 
   // If the receiver is a JSGlobalProxy this method will return its prototype,
   // otherwise the result is the receiver itself.
   inline Object* BypassGlobalProxy();
@@ skipping 7234 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_