Fix assertion in the debug agent.

src/debug-agent.cc

 // 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 381 matching lines @@
   conn->Send(buffer, len);
 
   // Send message body as UTF-8.
   int buffer_position = 0;  // Current buffer position.
   previous = unibrow::Utf16::kNoPreviousCharacter;
   for (int i = 0; i < message.length(); i++) {
     // Write next UTF-8 encoded character to buffer.
     uint16_t character = message[i];
     buffer_position +=
         unibrow::Utf8::Encode(buffer + buffer_position, character, previous);
-    ASSERT(buffer_position < kBufferSize);
+    ASSERT(buffer_position <= kBufferSize);
 
     // Send buffer if full or last character is encoded.
     if (kBufferSize - buffer_position <
           unibrow::Utf16::kMaxExtraUtf8BytesForOneUtf16CodeUnit ||
         i == message.length() - 1) {
       if (unibrow::Utf16::IsLeadSurrogate(character)) {
         const int kEncodedSurrogateLength =
             unibrow::Utf16::kUtf8BytesToCodeASurrogate;
         ASSERT(buffer_position >= kEncodedSurrogateLength);
         conn->Send(buffer, buffer_position - kEncodedSurrogateLength);
@@ skipping 47 matching lines @@
       return total_received;
     }
     total_received += received;
   }
   return total_received;
 }
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_DEBUGGER_SUPPORT