Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

ipc/mojo/async_handle_waiter.cc

 // 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.
 
 #include "ipc/mojo/async_handle_waiter.h"
 
 #include "base/atomic_ref_count.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/location.h"
@@ skipping 68 matching lines @@
 
   // IOObserver implementation:
 
   void WillProcessIOEvent() override {
     DCHECK(io_loop_level_ != 0 || !should_invoke_callback_);
     DCHECK_GE(io_loop_level_, 0);
     io_loop_level_++;
   }
 
   void DidProcessIOEvent() override {
+    // This object could have been constructed in another's class's
+    // DidProcessIOEvent.
+    if (io_loop_level_== 0)
+      return;
+
     DCHECK_GE(io_loop_level_, 1);
 
     // Leaving a nested loop.
     if (io_loop_level_ > 1) {
       io_loop_level_--;
       return;
     }
 
     // The zero |waiter_| indicates that |this| have lost the owner and can be
     // under destruction. So we cannot wrap it with a |scoped_refptr| anymore.
@@ skipping 57 matching lines @@
 void AsyncHandleWaiterContextTraits::Destruct(
     const AsyncHandleWaiter::Context* context) {
   context->io_runner_->PostTask(
       FROM_HERE,
       base::Bind(&base::DeletePointer<const AsyncHandleWaiter::Context>,
                  base::Unretained(context)));
 }
 
 }  // namespace internal
 }  // namespace IPC