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

mojo/edk/system/simple_dispatcher.cc

Index: mojo/edk/system/simple_dispatcher.cc
diff --git a/third_party/mojo/src/mojo/edk/system/simple_dispatcher.cc b/mojo/edk/system/simple_dispatcher.cc
similarity index 93%
copy from third_party/mojo/src/mojo/edk/system/simple_dispatcher.cc
copy to mojo/edk/system/simple_dispatcher.cc
index 7264a1219d596dcfbaccc861eed3c261f7dbcf6f..f7db8759aaf3f67b03becb9f4ddb0b38597f5b97 100644
--- a/third_party/mojo/src/mojo/edk/system/simple_dispatcher.cc
+++ b/mojo/edk/system/simple_dispatcher.cc
@@ -16,12 +16,12 @@ SimpleDispatcher::~SimpleDispatcher() {
 }
 
 void SimpleDispatcher::HandleSignalsStateChangedNoLock() {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
   awakable_list_.AwakeForStateChange(GetHandleSignalsStateImplNoLock());
 }
 
 void SimpleDispatcher::CancelAllAwakablesNoLock() {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
   awakable_list_.CancelAll();
 }
 
@@ -30,7 +30,7 @@ MojoResult SimpleDispatcher::AddAwakableImplNoLock(
     MojoHandleSignals signals,
     uint32_t context,
     HandleSignalsState* signals_state) {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
 
   HandleSignalsState state(GetHandleSignalsStateImplNoLock());
   if (state.satisfies(signals)) {
@@ -51,7 +51,7 @@ MojoResult SimpleDispatcher::AddAwakableImplNoLock(
 void SimpleDispatcher::RemoveAwakableImplNoLock(
     Awakable* awakable,
     HandleSignalsState* signals_state) {
-  mutex().AssertHeld();
+  lock().AssertAcquired();
   awakable_list_.Remove(awakable);
   if (signals_state)
     *signals_state = GetHandleSignalsStateImplNoLock();