Make the assumption on the minimum buffer size for GetLogLines explicit.

src/log-utils.h

 // Copyright 2006-2009 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 97 matching lines @@
 
   // See description in include/v8.h.
   static int GetLogLines(int from_pos, char* dest_buf, int max_size);
 
   // Returns whether logging is enabled.
   static bool IsEnabled() {
     return !is_stopped_ && (output_handle_ != NULL || output_buffer_ != NULL);
   }
 
   // Size of buffer used for formatting log messages.
-  static const int kMessageBufferSize = 2048;
+  static const int kMessageBufferSize = v8::V8::kMinimumSizeForLogLinesBuffer;
 
  private:
   typedef int (*WritePtr)(const char* msg, int length);
 
   // Initialization function called from Open... functions.
   static void Init();
 
   // Write functions assume that mutex_ is acquired by the caller.
   static WritePtr Write;
 
@@ skipping 151 matching lines @@
 
   ScopedLock sl;
   int pos_;
 };
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal
 
 #endif  // V8_LOG_UTILS_H_