Move QuicBufferAllocator into its own .cc/.h. No behavior change.

net/quic/core/quic_buffer_allocator.h

Index: net/quic/core/quic_buffer_allocator.h
diff --git a/net/quic/core/quic_buffer_allocator.h b/net/quic/core/quic_buffer_allocator.h
new file mode 100644
index 0000000000000000000000000000000000000000..d9b878ad19d6062314dbadd30f002a2609aa0d47
--- /dev/null
+++ b/net/quic/core/quic_buffer_allocator.h
@@ -0,0 +1,37 @@
+// 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.
+
+#ifndef NET_QUIC_QUIC_BUFFER_ALLOCATOR_H_
+#define NET_QUIC_QUIC_BUFFER_ALLOCATOR_H_
+
+#include <stddef.h>
+
+#include "net/base/net_export.h"
+
+namespace net {
+
+// Abstract base class for classes which allocate and delete buffers.
+class NET_EXPORT_PRIVATE QuicBufferAllocator {
+ public:
+  virtual ~QuicBufferAllocator();
+
+  // Returns or allocates a new buffer of |size|. Never returns null.
+  virtual char* New(size_t size) = 0;
+
+  // Returns or allocates a new buffer of |size| if |flag_enable| is true.
+  // Otherwise, returns a buffer that is compatible with this class directly
+  // with operator new. Never returns null.
+  virtual char* New(size_t size, bool flag_enable) = 0;
+
+  // Releases a buffer.
+  virtual void Delete(char* buffer) = 0;
+
+  // Marks the allocator as being idle. Serves as a hint to notify the allocator
+  // that it should release any resources it's still holding on to.
+  virtual void MarkAllocatorIdle() {}
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_QUIC_BUFFER_ALLOCATOR_H_