Add allocator interface for use by cdm_adapter

media/cdm/simple_cdm_buffer.cc

+// Copyright 2015 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 "media/cdm/simple_cdm_buffer.h"
+
+#include "base/logging.h"
+
+namespace media {
+
+// static
+SimpleCdmBuffer* SimpleCdmBuffer::Create(uint32_t capacity) {
+  DCHECK(capacity);
+  return new SimpleCdmBuffer(capacity);
+}
+
+SimpleCdmBuffer::SimpleCdmBuffer(uint32_t capacity)
+    : buffer_(capacity), size_(0) {}
+
+SimpleCdmBuffer::~SimpleCdmBuffer() {}
+
+void SimpleCdmBuffer::Destroy() {
+  delete this;
+}
+
+uint32_t SimpleCdmBuffer::Capacity() const {
+  return buffer_.size();
+}
+
+uint8_t* SimpleCdmBuffer::Data() {
+  return buffer_.data();
+}
+
+void SimpleCdmBuffer::SetSize(uint32_t size) {
+  DCHECK(size <= Capacity());
+  size_ = size > Capacity() ? 0 : size;
+}
+
+uint32_t SimpleCdmBuffer::Size() const {
+  return size_;
+}
+
+}  // namespace media