Add ownership edges between HostSharedBitmap and shared memory

base/memory/shared_memory_posix.cc

 // 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.
 
 #include "base/memory/shared_memory.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <stddef.h>
 #include <sys/mman.h>
@@ skipping 377 matching lines @@
   new_handle->auto_close = true;
 
   if (close_self) {
     Unmap();
     Close();
   }
 
   return true;
 }
 
-bool SharedMemory::GetUniqueId(SharedMemory::UniqueId* id) const {
+// static
+bool SharedMemory::GetUniqueId(const SharedMemoryHandle& handle,
+                               SharedMemory::UniqueId* id) {
   // This function is called just after mmap. fstat is a system call that might
   // cause I/O. It's safe to call fstat here because mmap for shared memory is
   // called in two cases:
   // 1) To handle file-mapped memory
   // 2) To handle annonymous shared memory
   // In 1), I/O is already permitted. In 2), the backend is on page cache and
   // fstat doesn't cause I/O access to the disk. See the discussion at
   // crbug.com/604726#c41.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
   struct stat file_stat;
-  if (HANDLE_EINTR(::fstat(static_cast<int>(handle().fd), &file_stat)) != 0)
+  if (HANDLE_EINTR(::fstat(static_cast<int>(handle.fd), &file_stat)) != 0)
     return false;
   id->first = file_stat.st_dev;
   id->second = file_stat.st_ino;
   return true;
 }
 
 }  // namespace base