Fix Windows build. My mistake for not trying it our prior to submitting.

src/log-utils.cc

 // Copyright 2009 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 298 matching lines @@
   }
 }
 
 
 void LogMessageBuilder::AppendStringPart(const char* str, int len) {
   if (pos_ + len > Log::kMessageBufferSize) {
     len = Log::kMessageBufferSize - pos_;
     ASSERT(len >= 0);
     if (len == 0) return;
   }
-  strncpy(Log::message_buffer_ + pos_, str, len);
+  Vector<char> buf(Log::message_buffer_ + pos_,
+                   Log::kMessageBufferSize - pos_);
+  OS::StrNCpy(buf, str, len);
   pos_ += len;
   ASSERT(pos_ <= Log::kMessageBufferSize);
 }
 
 
 bool LogMessageBuilder::StoreInCompressor(LogRecordCompressor* compressor) {
   return compressor->Store(Vector<const char>(Log::message_buffer_, pos_));
 }
 
 
@@ skipping 162 matching lines @@
     PrintBackwardReference(backref, best.distance, best.copy_from_pos);
     ASSERT(strlen(backref.start()) - best.backref_size == 0);
     prev_record->Truncate(unchanged_len + best.backref_size);
   }
   return true;
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal