GN: aix port along with linux_s390x, linux_ppc64 and linux_ppc64le support.

base/files/file_enumerator_posix.cc

 // Copyright (c) 2013 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.
 
 #include "base/files/file_enumerator.h"
 
 #include <dirent.h>
 #include <errno.h>
 #include <fnmatch.h>
 #include <stdint.h>
@@ skipping 108 matching lines @@
 }
 
 bool FileEnumerator::ReadDirectory(std::vector<FileInfo>* entries,
                                    const FilePath& source, bool show_links) {
   base::ThreadRestrictions::AssertIOAllowed();
   DIR* dir = opendir(source.value().c_str());
   if (!dir)
     return false;
 
 #if !defined(OS_LINUX) && !defined(OS_MACOSX) && !defined(OS_BSD) && \
-    !defined(OS_SOLARIS) && !defined(OS_ANDROID)
-  #error Port warning: depending on the definition of struct dirent, \
+    !defined(OS_SOLARIS) && !defined(OS_ANDROID) && !defined(OS_AIX)
+#error Port warning: depending on the definition of struct dirent, \
          additional space for pathname may be needed
 #endif
 
   struct dirent dent_buf;
   struct dirent* dent;
   while (readdir_r(dir, &dent_buf, &dent) == 0 && dent) {
     FileInfo info;
     info.filename_ = FilePath(dent->d_name);
 
     FilePath full_name = source.Append(dent->d_name);
@@ skipping 12 matching lines @@
       memset(&info.stat_, 0, sizeof(info.stat_));
     }
     entries->push_back(info);
   }
 
   closedir(dir);
   return true;
 }
 
 }  // namespace base