Componentize renderer side of DNS prefetching.

components/dns_prefetch/renderer/predictor_queue.h

 // Copyright (c) 2011 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.
 
 // DnsQueue is implemented as an almost FIFO circular buffer for text
 // strings that don't have embedded nulls ('\0').  The "almost" element is that
 // some duplicate strings may be removed (i.e., the string won't really be
 // pushed *if* the class happens to notice that a duplicate is already in the
 // queue).
 // The buffers internal format is null terminated character strings
 // (a.k.a., c_strings).
 // It is written to be as fast as possible during push() operations, so
 // that there will be minimal performance impact on a supplier thread.
 // The push() operation will not block, and no memory allocation is involved
 // (internally) during the push operations.
 // The one caveat is that if there is insufficient space in the buffer to
 // accept additional string via a push(), then the push() will fail, and
 // the buffer will be unmodified.
 
 // This class was designed for use in DNS prefetch operations.  During
 // rendering, the supplier is the renderer (typically), and the consumer
 // is a thread that sends messages to an async DNS resolver.
 
-#ifndef CHROME_RENDERER_NET_PREDICTOR_QUEUE_H__
-#define CHROME_RENDERER_NET_PREDICTOR_QUEUE_H__
+#ifndef COMPONENTS_DNS_PREFETCH_RENDERER_PREDICTOR_QUEUE_H__
+#define COMPONENTS_DNS_PREFETCH_RENDERER_PREDICTOR_QUEUE_H__
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 
+namespace dns_prefetch {
+
 class DnsQueue {
  public:
   // BufferSize is a signed type used for indexing into a buffer.
   typedef int32 BufferSize;
 
   enum PushResult { SUCCESSFUL_PUSH, OVERFLOW_PUSH, REDUNDANT_PUSH };
 
   // The size specified in the constructor creates a buffer large enough
   // to hold at most one string of that length, or "many"
   // strings of considerably shorter length.  Note that strings
@@ skipping 35 matching lines @@
   // If writable_ == readable_, then the buffer is empty.
   BufferSize readable_;  // Next readable char in buffer_.
   BufferSize writeable_;  // The next space in buffer_ to push.
 
   // Number of queued strings
   size_t size_;
 
   DISALLOW_COPY_AND_ASSIGN(DnsQueue);
 };  // class DnsQueue
 
-#endif  // CHROME_RENDERER_NET_PREDICTOR_QUEUE_H__
+}  // namespace dns_prefetch
+
+#endif  // COMPONENTS_DNS_PREFETCH_RENDERER_PREDICTOR_QUEUE_H__