make base::SharedMemoryHandle a class on POSIX.

base/memory/discardable_shared_memory.cc

 // Copyright 2014 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/discardable_shared_memory.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 
@@ skipping 206 matching lines @@
   DCHECK_EQ(locked_pages_.size(), locked_page_count_);
 #endif
 
   // Always behave as if memory was purged when trying to lock a 0 byte segment.
   if (!length)
       return PURGED;
 
 // Pin pages if supported.
 #if defined(OS_ANDROID)
   SharedMemoryHandle handle = shared_memory_.handle();
-  if (SharedMemory::IsHandleValid(handle)) {
-    if (ashmem_pin_region(
-            handle.fd, AlignToPageSize(sizeof(SharedState)) + offset, length)) {
+  if (handle.IsValid()) {
+    if (ashmem_pin_region(handle.GetHandle(),
+                          AlignToPageSize(sizeof(SharedState)) + offset,
+                          length)) {
       return PURGED;
     }
   }
 #endif
 
   return SUCCESS;
 }
 
 void DiscardableSharedMemory::Unlock(size_t offset, size_t length) {
   DCHECK_EQ(AlignToPageSize(offset), offset);
   DCHECK_EQ(AlignToPageSize(length), length);
 
   // Calls to this function must be synchronized properly.
   DFAKE_SCOPED_LOCK(thread_collision_warner_);
 
   // Zero for length means "everything onward".
   if (!length)
     length = AlignToPageSize(mapped_size_) - offset;
 
   DCHECK(shared_memory_.memory());
 
 // Unpin pages if supported.
 #if defined(OS_ANDROID)
   SharedMemoryHandle handle = shared_memory_.handle();
-  if (SharedMemory::IsHandleValid(handle)) {
-    if (ashmem_unpin_region(
-            handle.fd, AlignToPageSize(sizeof(SharedState)) + offset, length)) {
+  if (handle.IsValid()) {
+    if (ashmem_unpin_region(handle.GetHandle(),
+                            AlignToPageSize(sizeof(SharedState)) + offset,
+                            length)) {
       DPLOG(ERROR) << "ashmem_unpin_region() failed";
     }
   }
 #endif
 
   size_t start = offset / base::GetPageSize();
   size_t end = start + length / base::GetPageSize();
   DCHECK_LE(start, end);
   DCHECK_LE(end, AlignToPageSize(mapped_size_) / base::GetPageSize());
 
@@ skipping 128 matching lines @@
 
 void DiscardableSharedMemory::Close() {
   shared_memory_.Close();
 }
 
 Time DiscardableSharedMemory::Now() const {
   return Time::Now();
 }
 
 }  // namespace base