Show the callstack that a nontransferable message pipe was first used if it's erroneously sent later

mojo/edk/system/message_pipe_dispatcher.h

 // 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.
 
 #ifndef MOJO_EDK_SYSTEM_MESSAGE_PIPE_DISPATCHER_H_
 #define MOJO_EDK_SYSTEM_MESSAGE_PIPE_DISPATCHER_H_
 
 #include "base/memory/ref_counted.h"
 #include "mojo/edk/embedder/platform_channel_pair.h"
 #include "mojo/edk/system/awakable_list.h"
 #include "mojo/edk/system/dispatcher.h"
 #include "mojo/edk/system/message_in_transit_queue.h"
 #include "mojo/edk/system/raw_channel.h"
 #include "mojo/edk/system/system_impl_export.h"
 #include "mojo/public/cpp/system/macros.h"
 
+namespace base {
+namespace debug {
+class StackTrace;
+}
+}
+
 namespace mojo {
 namespace edk {
 
 // This is the |Dispatcher| implementation for message pipes (created by the
 // Mojo primitive |MojoCreateMessagePipe()|). This class is thread-safe.
 class MOJO_SYSTEM_IMPL_EXPORT MessagePipeDispatcher final
     : public Dispatcher, public RawChannel::Delegate {
  public:
   // The default options to use for |MojoCreateMessagePipe()|. (Real uses
   // should obtain this via |ValidateCreateOptions()| with a null |in_options|;
@@ skipping 107 matching lines @@
   // "binds" the pipe id to this object.
   void RequestNontransferableChannel();
 
   // Protected by |lock()|:
   RawChannel* channel_;
 
   // Queue of incoming messages that we read from RawChannel but haven't been
   // consumed through MojoReadMessage yet.
   MessageInTransitQueue message_queue_;
 
-  // The following members are only used when transferable_ is false;
+  // The following members are only used when transferable_ is true;
 
   // When sending MP, contains serialized message_queue_.
   std::vector<char> serialized_message_queue_;
   std::vector<char> serialized_read_buffer_;
   std::vector<char> serialized_write_buffer_;
   // Contains FDs from (in this order): the read buffer, the write buffer, and
   // message queue.
   std::vector<int> serialized_fds_;
   size_t serialized_read_fds_length_;
   size_t serialized_write_fds_length_;
   size_t serialized_message_fds_length_;
   ScopedPlatformHandle serialized_platform_handle_;
 
-  // The following members are only used when transferable_ is true;
+  // The following members are only used when transferable_ is false;
 
   // The unique id shared by both ends of a non-transferable message pipe. This
   // is held on until a read or write are done, and at that point it's used to
   // get a RawChannel.
   uint64_t pipe_id_;
   enum NonTransferableState {
     WAITING_FOR_READ_OR_WRITE,
     CONNECT_CALLED,
     CONNECTED,
     WAITING_FOR_CONNECT_TO_CLOSE,
     CLOSED,
     SERIALISED,
   };
 
   NonTransferableState non_transferable_state_;
   // Messages that were written while we were waiting to get a RawChannel.
   MessageInTransitQueue non_transferable_outgoing_message_queue_;
+  scoped_ptr<base::debug::StackTrace> non_transferable_bound_stack_;
 
 
   // The following members are used for both modes of transferable_.
 
   AwakableList awakable_list_;
 
   // If DispatcherTransport is created. Must be set before lock() is called to
   // avoid deadlocks with RawChannel calling us.
   base::Lock started_transport_;
 
   bool serialized_;
   bool calling_init_;
   bool write_error_;
   // Whether it can be sent after read or write.
   bool transferable_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(MessagePipeDispatcher);
 };
 
 }  // namespace edk
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_MESSAGE_PIPE_DISPATCHER_H_