rename some base _linux files to _posix so that others can use it too

base/native_library_linux.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 "base/native_library.h"
-
-#include <dlfcn.h>
-
-#include "base/file_path.h"
-#include "base/logging.h"
-#include "base/threading/thread_restrictions.h"
-#include "base/utf_string_conversions.h"
-
-namespace base {
-
-// static
-NativeLibrary LoadNativeLibrary(const FilePath& library_path,
-                                std::string* error) {
-  // dlopen() opens the file off disk.
-  base::ThreadRestrictions::AssertIOAllowed();
-
-  // We deliberately do not use RTLD_DEEPBIND.  For the history why, please
-  // refer to the bug tracker.  Some useful bug reports to read include:
-  // http://crbug.com/17943, http://crbug.com/17557, http://crbug.com/36892,
-  // and http://crbug.com/40794.
-  void* dl = dlopen(library_path.value().c_str(), RTLD_LAZY);
-  if (!dl && error)
-    *error = dlerror();
-
-  return dl;
-}
-
-// static
-void UnloadNativeLibrary(NativeLibrary library) {
-  int ret = dlclose(library);
-  if (ret < 0) {
-    DLOG(ERROR) << "dlclose failed: " << dlerror();
-    NOTREACHED();
-  }
-}
-
-// static
-void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
-                                          const char* name) {
-  return dlsym(library, name);
-}
-
-// static
-string16 GetNativeLibraryName(const string16& name) {
-  return ASCIIToUTF16("lib") + name + ASCIIToUTF16(".so");
-}
-
-}  // namespace base