[mojo-edk] Add MojoWatch and MojoCancelWatch APIs

mojo/edk/system/shared_buffer_dispatcher.cc

Index: mojo/edk/system/shared_buffer_dispatcher.cc
diff --git a/mojo/edk/system/shared_buffer_dispatcher.cc b/mojo/edk/system/shared_buffer_dispatcher.cc
index 1805a926019a9a85ec1701dd680283ba32a6654d..d3c9f2eb6b258ea57c2854e5608413522d84b979 100644
--- a/mojo/edk/system/shared_buffer_dispatcher.cc
+++ b/mojo/edk/system/shared_buffer_dispatcher.cc
@@ -154,7 +154,7 @@ Dispatcher::Type SharedBufferDispatcher::GetType() const {
   return Type::SHARED_BUFFER;
 }
 
-MojoResult SharedBufferDispatcher::Close() {
+MojoResult SharedBufferDispatcher::Close(RequestContext* request_context) {
   base::AutoLock lock(lock_);
   if (in_transit_)
     return MOJO_RESULT_INVALID_ARGUMENT;
@@ -231,7 +231,7 @@ bool SharedBufferDispatcher::EndSerialize(void* destination,
   return true;
 }
 
-bool SharedBufferDispatcher::BeginTransit() {
+bool SharedBufferDispatcher::BeginTransit(RequestContext* request_context) {
   base::AutoLock lock(lock_);
   if (in_transit_)
     return false;
@@ -239,14 +239,16 @@ bool SharedBufferDispatcher::BeginTransit() {
   return in_transit_;
 }
 
-void SharedBufferDispatcher::CompleteTransitAndClose() {
+void SharedBufferDispatcher::CompleteTransitAndClose(
+    RequestContext* request_context) {
   base::AutoLock lock(lock_);
   in_transit_ = false;
   shared_buffer_ = nullptr;
   ignore_result(handle_for_transit_.release());
 }
 
-void SharedBufferDispatcher::CancelTransit() {
+void SharedBufferDispatcher::CancelTransit(
+    RequestContext* request_context) {
   base::AutoLock lock(lock_);
   in_transit_ = false;
   handle_for_transit_.reset();