This makes selenium in Firefox work on the Mac.

serializer/cross/serializer.cc

 /*
  * Copyright 2009, Google Inc.
  * 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.
@@ skipping 306 matching lines @@
   }
 
   void Visit(Skin* skin) {
     Visit(static_cast<NamedObject*>(skin));
 
     if (!binary_) {
       writer_->WritePropertyName("influences");
       writer_->BeginCompacting();
       writer_->OpenArray();
       const Skin::InfluencesArray& influences_array = skin->influences();
-      for (int i = 0; i != influences_array.size(); ++i) {
+      for (Skin::InfluencesArray::size_type i = 0; i != influences_array.size(); ++i) {
         const Skin::Influences& influences = influences_array[i];
         writer_->OpenArray();
-        for (int j = 0; j != influences.size(); ++j) {
+        for (Skin::Influences::size_type j = 0; j != influences.size(); ++j) {
           const Skin::Influence& influence = influences[j];
           Serialize(writer_, influence.matrix_index);
           Serialize(writer_, influence.weight);
         }
         writer_->CloseArray();
       }
       writer_->CloseArray();
       writer_->EndCompacting();
     }
 
@@ skipping 597 matching lines @@
 
 void Serializer::SerializeSection(ObjectBase* object, Section section) {
   DCHECK(section >= 0 && section < NUM_SECTIONS);
   sections_[section].visitor_->Accept(object);
 }
 
 void Serializer::SerializeParam(Param* param) {
   param_visitor_->Accept(param);
 }
 }  // namespace o3d