Factor out the code to write control frame headers into a new constructor of SpdyFrameBuilder.

net/spdy/spdy_frame_builder.h

 // 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_SPDY_SPDY_FRAME_BUILDER_H_
 #define NET_SPDY_SPDY_FRAME_BUILDER_H_
 #pragma once
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/string_piece.h"
 #include "base/sys_byteorder.h"
 #include "net/base/net_export.h"
 #include "net/spdy/spdy_protocol.h"
 
 namespace net {
 
 // This class provides facilities for basic binary value packing and unpacking
 // into Spdy frames.
 //
 // The SpdyFrameBuilder supports appending primitive values (int, string, etc)
 // to a frame instance.  The SpdyFrameBuilder grows its internal memory buffer
 // dynamically to hold the sequence of primitive values.   The internal memory
 // buffer is exposed as the "data" of the SpdyFrameBuilder.
 class NET_EXPORT_PRIVATE SpdyFrameBuilder {
  public:
   ~SpdyFrameBuilder();
 
-  SpdyFrameBuilder();
+  // Initializes a SpdyFrameBuilder with a buffer of given size,
+  // populate with a SPDY control frame header based
+  // on |type|, |flags|, and |spdy_version|.
+  SpdyFrameBuilder(SpdyControlType type, SpdyControlFlags flags,
+                   int spdy_version, size_t size);
 
-  // Initiailizes a SpdyFrameBuilder with a buffer of given size.
-  explicit SpdyFrameBuilder(size_t size);
+  // Initiailizes a SpdyFrameBuilder with a buffer of given size,
+  // populated with a SPDY data frame header based on
+  // |stream_id| and |flags|.
+  SpdyFrameBuilder(SpdyStreamId stream_id, SpdyDataFlags flags,  size_t size);
 
   // Returns the size of the SpdyFrameBuilder's data.
   int length() const { return length_; }
 
   // Takes the buffer from the SpdyFrameBuilder.
   SpdyFrame* take() {
     SpdyFrame* rv = new SpdyFrame(buffer_, true);
     buffer_ = NULL;
     capacity_ = 0;
     length_ = 0;
@@ skipping 74 matching lines @@
   char* BeginWrite(size_t length);
 
   char* buffer_;
   size_t capacity_;  // Allocation size of payload (or -1 if buffer is const).
   size_t length_;    // current length of the buffer
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_FRAME_BUILDER_H_