base: Rename discardable memory allocator interface and remove unnecessary class.

base/memory/discardable_memory_shmem.cc

Index: base/memory/discardable_memory_shmem.cc
diff --git a/base/memory/discardable_memory_shmem.cc b/base/memory/discardable_memory_shmem.cc
deleted file mode 100644
index 059d84ca6111a86deef41162ee6129fe41f5a77a..0000000000000000000000000000000000000000
--- a/base/memory/discardable_memory_shmem.cc
+++ /dev/null
@@ -1,50 +0,0 @@
-// 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_memory_shmem.h"
-
-#include "base/lazy_instance.h"
-#include "base/memory/discardable_memory_shmem_allocator.h"
-
-namespace base {
-namespace internal {
-
-DiscardableMemoryShmem::DiscardableMemoryShmem(size_t bytes)
-    : chunk_(DiscardableMemoryShmemAllocator::GetInstance()
-                 ->AllocateLockedDiscardableMemory(bytes)),
-      is_locked_(true) {
-  DCHECK(chunk_);
-}
-
-DiscardableMemoryShmem::~DiscardableMemoryShmem() {
-  if (is_locked_)
-    Unlock();
-}
-
-bool DiscardableMemoryShmem::Lock() {
-  DCHECK(!is_locked_);
-  DCHECK(chunk_);
-
-  if (!chunk_->Lock()) {
-    chunk_.reset();
-    return false;
-  }
-
-  is_locked_ = true;
-  return true;
-}
-
-void DiscardableMemoryShmem::Unlock() {
-  DCHECK(is_locked_);
-  chunk_->Unlock();
-  is_locked_ = false;
-}
-
-void* DiscardableMemoryShmem::Memory() const {
-  DCHECK(is_locked_);
-  return chunk_->Memory();
-}
-
-}  // namespace internal
-}  // namespace base