Fix debug name inferring wrt proxies

src/string-stream.cc

 // Copyright 2014 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/string-stream.h"
 
 #include "src/handles-inl.h"
 #include "src/prototype.h"
 
 namespace v8 {
@@ skipping 519 matching lines @@
   if (receiver->IsNull() || receiver->IsUndefined() || receiver->IsJSProxy()) {
     print_name = true;
   } else {
     if (!receiver->IsJSObject()) {
       receiver = receiver->GetRootMap(isolate)->prototype();
     }
 
     for (PrototypeIterator iter(isolate, JSObject::cast(receiver),
                                 PrototypeIterator::START_AT_RECEIVER);
          !iter.IsAtEnd(); iter.Advance()) {
+      if (iter.GetCurrent()->IsJSProxy()) break;
       Object* key = iter.GetCurrent<JSObject>()->SlowReverseLookup(fun);
       if (!key->IsUndefined()) {
         if (!name->IsString() ||
             !key->IsString() ||
             !String::cast(name)->Equals(String::cast(key))) {
           print_name = true;
         }
         if (name->IsString() && String::cast(name)->length() == 0) {
           print_name = false;
         }
@@ skipping 26 matching lines @@
   MemCopy(new_space, space_, *bytes);
   *bytes = new_bytes;
   DeleteArray(space_);
   space_ = new_space;
   return new_space;
 }
 
 
 }  // namespace internal
 }  // namespace v8