[mojo-edk] Add MojoWatch and MojoCancelWatch APIs

mojo/edk/system/wait_set_dispatcher.cc

Index: mojo/edk/system/wait_set_dispatcher.cc
diff --git a/mojo/edk/system/wait_set_dispatcher.cc b/mojo/edk/system/wait_set_dispatcher.cc
index a083ce961b3804640e55c06488af09a7f44c9ec9..231f1e84e5fdd00612a96650c6d4d229d45b2acb 100644
--- a/mojo/edk/system/wait_set_dispatcher.cc
+++ b/mojo/edk/system/wait_set_dispatcher.cc
@@ -43,7 +43,7 @@ Dispatcher::Type WaitSetDispatcher::GetType() const {
   return Type::WAIT_SET;
 }
 
-MojoResult WaitSetDispatcher::Close() {
+MojoResult WaitSetDispatcher::Close(RequestContext* request_context) {
   base::AutoLock lock(lock_);
 
   if (is_closed_)
@@ -278,7 +278,7 @@ void WaitSetDispatcher::RemoveAwakable(Awakable* awakable,
     *signals_state = GetHandleSignalsState();
 }
 
-bool WaitSetDispatcher::BeginTransit() {
+bool WaitSetDispatcher::BeginTransit(RequestContext* request_context) {
   // You can't transfer wait sets!
   return false;
 }