Last set of fixes to make the src/mojo/edk pass the page cycler.

mojo/edk/system/dispatcher.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/edk/system/dispatcher.h"
 
 #include "base/logging.h"
 #include "mojo/edk/system/configuration.h"
 #include "mojo/edk/system/data_pipe_consumer_dispatcher.h"
 #include "mojo/edk/system/data_pipe_producer_dispatcher.h"
@@ skipping 435 matching lines @@
   is_closed_ = true;
   CancelAllAwakablesNoLock();
   return CreateEquivalentDispatcherAndCloseImplNoLock();
 }
 
 void Dispatcher::StartSerialize(size_t* max_size,
                                 size_t* max_platform_handles) {
   DCHECK(max_size);
   DCHECK(max_platform_handles);
   DCHECK(!is_closed_);
+  base::AutoLock locker(lock_);
   StartSerializeImplNoLock(max_size, max_platform_handles);
 }
 
 bool Dispatcher::EndSerializeAndClose(void* destination,
                                       size_t* actual_size,
                                       PlatformHandleVector* platform_handles) {
   DCHECK(actual_size);
   DCHECK(!is_closed_);
 
   // Like other |...Close()| methods, we mark ourselves as closed before calling
   // the impl. But there's no need to cancel waiters: we shouldn't have any (and
   // shouldn't be in |Core|'s handle table.
   is_closed_ = true;
 
-#if !defined(NDEBUG)
-  // See the comment above |EndSerializeAndCloseImplNoLock()|. In brief: Locking
-  // isn't actually needed, but we need to satisfy assertions (which we don't
-  // want to remove or weaken).
   base::AutoLock locker(lock_);
-#endif
-
   return EndSerializeAndCloseImplNoLock(destination, actual_size,
                                         platform_handles);
 }
 
 // DispatcherTransport ---------------------------------------------------------
 
 void DispatcherTransport::End() {
   DCHECK(dispatcher_);
   dispatcher_->lock_.Release();
 
   dispatcher_->TransportEnded();
 
   dispatcher_ = nullptr;
 }
 
 }  // namespace edk
 }  // namespace mojo