Two chagnes to cast socket:

chrome/browser/extensions/api/cast_channel/cast_socket.h

 // Copyright 2013 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 CHROME_BROWSER_EXTENSIONS_API_CAST_CHANNEL_CAST_SOCKET_H_
 #define CHROME_BROWSER_EXTENSIONS_API_CAST_CHANNEL_CAST_SOCKET_H_
 
 #include <queue>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "chrome/browser/extensions/api/api_resource.h"
 #include "chrome/browser/extensions/api/api_resource_manager.h"
-#include "chrome/browser/extensions/api/cast_channel/cast_channel.pb.h"

[Wez, 2014/02/12 21:13:16]

How did this make the build flaky? Something including this header that did not
itself depend on the API protos?

[mark a. foltz, 2014/02/12 21:45:02]

The files generated from the IDL included the .pb.h, but didn't depend on the pb
target in GYP.  If the API target is built before the pb target the build
breaks.

[Munjal (Google), 2014/02/12 22:34:36]

It is complicated and hence took me a while to figure out.

So what happens is that generated_api.cc includes all files under extensions/api
that contain EXTENSION_FUNCTION macro defintion. The file generated_api.cc
itself is generated by a python script.

So generated_api.cc includes cast_channel_api.h, which includes cast_socket.h,
which includes cast_channel.pb.h. But cast_channel.pb.h is sometimes not yet
generated from proto buffer before generated_api.cc is compiled.

There are otehr approaches to fix this but this appears to be the cleanest.

 #include "chrome/common/extensions/api/cast_channel.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_log.h"
 #include "url/gurl.h"
 
 namespace net {
 class AddressList;
 class CertVerifier;
 class SSLClientSocket;
 class StreamSocket;
 class TCPClientSocket;
 class TransportSecurityState;
 }
 
 namespace extensions {
 namespace api {
 namespace cast_channel {
 
+class CastMessage;
+
 // Size (in bytes) of the largest allowed message payload on the wire (without
 // the header).
 extern const uint32 kMaxMessageSize;
 
 // Size (in bytes) of the message header.
 extern const uint32 kMessageHeaderSize;
 
 // This class implements a channel between Chrome and a Cast device using a TCP
 // socket. The channel may be unauthenticated (cast://) or authenticated
 // (casts://). All CastSocket objects must be used only on the IO thread.
@@ skipping 204 matching lines @@
 
   virtual bool CalledOnValidThread() const;
 
   base::ThreadChecker thread_checker_;
 
   // The id of the channel.
   int channel_id_;
 
   // The URL of the peer (cast:// or casts://).
   GURL url_;
+  // String used in log messages for url.

[Wez, 2014/02/12 21:13:16]

Suggest renaming this to |log_prefix_| - you could then do without a
description, but if you prefer to keep one I'd suggest "String containing the
peer's URL, to prefix to all log messages".

[Munjal (Google), 2014/02/12 22:34:36]

Done.

[Munjal (Google), 2014/02/12 22:34:36]

Done.

+  std::string url_log_str_;
   // Delegate to inform of incoming messages and errors.
   Delegate* delegate_;
   // True if receiver authentication should be performed.
   bool auth_required_;
   // The IP endpoint of the peer.
   net::IPEndPoint ip_endpoint_;
 
   // IOBuffer for reading the message header.
   scoped_refptr<net::GrowableIOBuffer> header_read_buffer_;
   // IOBuffer for reading the message body.
   scoped_refptr<net::GrowableIOBuffer> body_read_buffer_;
   // IOBuffer to currently read into.
   scoped_refptr<net::GrowableIOBuffer> current_read_buffer_;
   // The number of bytes in the current message body.
   uint32 current_message_size_;
   // Last message received on the socket.
-  CastMessage current_message_;
+  scoped_ptr<CastMessage> current_message_;
 
   // The NetLog for this service.
   net::NetLog* net_log_;
   // The NetLog source for this service.
   net::NetLog::Source net_log_source_;
 
   // CertVerifier is owned by us but should be deleted AFTER SSLClientSocket
   // since in some cases the destructor of SSLClientSocket may call a method
   // to cancel a cert verification request.
   scoped_ptr<net::CertVerifier> cert_verifier_;
@@ skipping 60 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(CastSocketTest, TestReadMany);
   FRIEND_TEST_ALL_PREFIXES(CastSocketTest, TestFullSecureConnectionFlowAsync);
   DISALLOW_COPY_AND_ASSIGN(CastSocket);
 };
 
 }  // namespace cast_channel
 }  // namespace api
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_CAST_CHANNEL_CAST_SOCKET_H_