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

mojo/edk/js/waiting_callback.cc

Index: mojo/edk/js/waiting_callback.cc
diff --git a/third_party/mojo/src/mojo/edk/js/waiting_callback.cc b/mojo/edk/js/waiting_callback.cc
similarity index 98%
copy from third_party/mojo/src/mojo/edk/js/waiting_callback.cc
copy to mojo/edk/js/waiting_callback.cc
index d5c48c539e346002d7c7b6d8c7dd71cc1e479111..0bc875dd1a912672077a050ef86ae7b1d73c6f1e 100644
--- a/third_party/mojo/src/mojo/edk/js/waiting_callback.cc
+++ b/mojo/edk/js/waiting_callback.cc
@@ -10,7 +10,7 @@
 #include "mojo/public/cpp/environment/environment.h"
 
 namespace mojo {
-namespace js {
+namespace edk {
 
 namespace {
 
@@ -111,5 +111,5 @@ void WaitingCallback::OnWillCloseHandle() {
                  MOJO_RESULT_INVALID_ARGUMENT));
 }
 
-}  // namespace js
+}  // namespace edk
 }  // namespace mojo