Linux: add an option to use system minizip.

chrome/common/zip_internal.cc

 // Copyright (c) 2011 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 "chrome/common/zip.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/utf_string_conversions.h"
+
+#if defined(USE_SYSTEM_MINIZIP)
+#include <minizip/unzip.h>
+#include <minizip/zip.h>
+#include <minizip/ioapi.h>
+#else
 #include "third_party/zlib/contrib/minizip/unzip.h"
 #include "third_party/zlib/contrib/minizip/zip.h"
 #if defined(OS_WIN)
 #include "third_party/zlib/contrib/minizip/iowin32.h"
 #elif defined(OS_POSIX)
 #include "third_party/zlib/contrib/minizip/ioapi.h"
-#endif
+#endif  // defined(OS_POSIX)
+#endif  // defined(USE_SYSTEM_MINIZIP)
 
 namespace {
 
 #if defined(OS_WIN)
 typedef struct {
   HANDLE hf;
   int error;
 } WIN32FILE_IOWIN;
 
 // This function is derived from third_party/minizip/iowin32.c.
@@ skipping 236 matching lines @@
   zip_func_ptrs = &zip_funcs;
 #endif
   return zipOpen2(file_name_utf8.c_str(),
                   append_flag,
                   NULL,  // global comment
                   zip_func_ptrs);
 }
 
 }  // namespace internal
 }  // namespace zip