Fix Mario (32-bit) build.

sandbox/linux/suid/process_util_linux.c

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // The following is the C version of code from base/process_utils_linux.cc.
 // We shouldn't link against C++ code in a setuid binary.
 
 #define _GNU_SOURCE  // needed for O_DIRECTORY
 
 #include "process_util.h"
@@ skipping 76 matching lines @@
   char value[21];
   switch (margin_mb) {
     case -1L:
       snprintf(value, sizeof(value), "off");
       break;
     case 0L:
     case 25L:
     case 50L:
     case 100L:
     case 200L:
-      snprintf(value, sizeof(value), "%zu", margin_mb);
+      snprintf(value, sizeof(value), "%lld", (long long int)margin_mb);
       break;
     default:
       return false;
   }
 
   bool success = (write(file_descriptor, value, strlen(value)) >= 0);
   close(file_descriptor);
   return success;
 }