[mojo-edk] Add explicit message object APIs

mojo/public/cpp/bindings/lib/connector.cc

 // 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.
 
 #include "mojo/public/cpp/bindings/lib/connector.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 142 matching lines @@
       WriteMessageRaw(message_pipe_.get(),
                       message->data(),
                       message->data_num_bytes(),
                       message->mutable_handles()->empty()
                           ? nullptr
                           : reinterpret_cast<const MojoHandle*>(
                                 &message->mutable_handles()->front()),
                       static_cast<uint32_t>(message->mutable_handles()->size()),
                       MOJO_WRITE_MESSAGE_FLAG_NONE);
 
+  // The handles are always either transferred or closed, so we don't need the
+  // message to track their lifetime any longer.
+  message->mutable_handles()->clear();
+
   switch (rv) {
     case MOJO_RESULT_OK:
-      // The handles were successfully transferred, so we don't need the message
-      // to track their lifetime any longer.
-      message->mutable_handles()->clear();
       break;
     case MOJO_RESULT_FAILED_PRECONDITION:
       // There's no point in continuing to write to this pipe since the other
       // end is gone. Avoid writing any future messages. Hide write failures
       // from the caller since we'd like them to continue consuming any backlog
       // of incoming messages before regarding the message pipe as closed.
       drop_writes_ = true;
       break;
     case MOJO_RESULT_BUSY:
       // We'd get a "busy" result if one of the message's handles is:
@@ skipping 179 matching lines @@
   if (sync_watcher_)
     return;
   sync_watcher_.reset(new SyncHandleWatcher(
       message_pipe_.get(), MOJO_HANDLE_SIGNAL_READABLE,
       base::Bind(&Connector::OnSyncHandleWatcherHandleReady,
                  base::Unretained(this))));
 }
 
 }  // namespace internal
 }  // namespace mojo