[mojo-edk] Add MojoWatch and MojoCancelWatch APIs

mojo/edk/embedder/entrypoints.cc

Index: mojo/edk/embedder/entrypoints.cc
diff --git a/mojo/edk/embedder/entrypoints.cc b/mojo/edk/embedder/entrypoints.cc
index 102b25f87cd5034574d9b01f9fbb24e378a0a6e1..23b919da7b41e9dbebcce64a82dd90e46fb1645b 100644
--- a/mojo/edk/embedder/entrypoints.cc
+++ b/mojo/edk/embedder/entrypoints.cc
@@ -42,6 +42,17 @@ MojoResult MojoWaitMany(const MojoHandle* handles,
                           signals_states);
 }
 
+MojoResult MojoWatch(MojoHandle handle,
+                     MojoHandleSignals signals,
+                     MojoWatchCallback callback,
+                     uintptr_t context) {
+  return g_core->Watch(handle, signals, callback, context);
+}
+
+MojoResult MojoCancelWatch(MojoHandle handle, uintptr_t context) {
+  return g_core->CancelWatch(handle, context);
+}
+
 MojoResult MojoCreateWaitSet(MojoHandle* wait_set_handle) {
   return g_core->CreateWaitSet(wait_set_handle);
 }