Port visitedlink tests to Linux. Also make them pass on Linux, which

base/shared_memory_win.cc

 // Copyright (c) 2006-2008 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/shared_memory.h"
 
 #include "base/logging.h"
 #include "base/win_util.h"
 
 namespace base {
@@ skipping 32 matching lines @@
   Close();
   if (lock_ != NULL)
     CloseHandle(lock_);
 }
 
 // static
 bool SharedMemory::IsHandleValid(const SharedMemoryHandle& handle) {
   return handle != NULL;
 }
 
+// static
+SharedMemoryHandle SharedMemory::NULLHandle() {
+  return NULL;
+}
+
 bool SharedMemory::Create(const std::wstring &name, bool read_only,
                           bool open_existing, size_t size) {
   DCHECK(mapped_file_ == NULL);
 
   name_ = name;
   read_only_ = read_only;
   mapped_file_ = CreateFileMapping(INVALID_HANDLE_VALUE, NULL,
       read_only_ ? PAGE_READONLY : PAGE_READWRITE, 0, static_cast<DWORD>(size),
       name.empty() ? NULL : name.c_str());
   if (!mapped_file_)
@@ skipping 108 matching lines @@
 void SharedMemory::Unlock() {
   DCHECK(lock_ != NULL);
   ReleaseMutex(lock_);
 }
 
 SharedMemoryHandle SharedMemory::handle() const {
   return mapped_file_;
 }
 
 }  // namespace base