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

mojo/edk/js/waiting_callback.h

Index: mojo/edk/js/waiting_callback.h
diff --git a/third_party/mojo/src/mojo/edk/js/waiting_callback.h b/mojo/edk/js/waiting_callback.h
similarity index 84%
copy from third_party/mojo/src/mojo/edk/js/waiting_callback.h
copy to mojo/edk/js/waiting_callback.h
index 63f4d0cab3d56d0d7c0ea3748ab69526e04c6d42..c1b76aaf47e6afc2bf6e330d8f348d6534286548 100644
--- a/third_party/mojo/src/mojo/edk/js/waiting_callback.h
+++ b/mojo/edk/js/waiting_callback.h
@@ -2,20 +2,20 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef THIRD_PARTY_MOJO_SRC_MOJO_EDK_JS_WAITING_CALLBACK_H_
-#define THIRD_PARTY_MOJO_SRC_MOJO_EDK_JS_WAITING_CALLBACK_H_
+#ifndef MOJO_EDK_JS_WAITING_CALLBACK_H_
+#define MOJO_EDK_JS_WAITING_CALLBACK_H_
 
 #include "base/memory/weak_ptr.h"
 #include "gin/handle.h"
 #include "gin/runner.h"
 #include "gin/wrappable.h"
+#include "mojo/edk/js/handle.h"
+#include "mojo/edk/js/handle_close_observer.h"
 #include "mojo/public/c/environment/async_waiter.h"
 #include "mojo/public/cpp/system/core.h"
-#include "third_party/mojo/src/mojo/edk/js/handle.h"
-#include "third_party/mojo/src/mojo/edk/js/handle_close_observer.h"
 
 namespace mojo {
-namespace js {
+namespace edk {
 
 class WaitingCallback : public gin::Wrappable<WaitingCallback>,
                         public HandleCloseObserver {
@@ -62,7 +62,7 @@ class WaitingCallback : public gin::Wrappable<WaitingCallback>,
   DISALLOW_COPY_AND_ASSIGN(WaitingCallback);
 };
 
-}  // namespace js
+}  // namespace edk
 }  // namespace mojo
 
-#endif  // THIRD_PARTY_MOJO_SRC_MOJO_EDK_JS_WAITING_CALLBACK_H_
+#endif  // MOJO_EDK_JS_WAITING_CALLBACK_H_