EDK: Change Awakable::Awake()'s context, etc., to be a uint64_t.

mojo/edk/system/data_pipe.cc

Index: mojo/edk/system/data_pipe.cc
diff --git a/mojo/edk/system/data_pipe.cc b/mojo/edk/system/data_pipe.cc
index 4a6d5ae0ba3956d6df54fc40700916ef17c5c5a4..d74cba8759839b4dfcbd01f8776a21edd284f7d4 100644
--- a/mojo/edk/system/data_pipe.cc
+++ b/mojo/edk/system/data_pipe.cc
@@ -399,7 +399,7 @@ HandleSignalsState DataPipe::ProducerGetHandleSignalsState() {
 
 MojoResult DataPipe::ProducerAddAwakable(Awakable* awakable,
                                          MojoHandleSignals signals,
-                                         uint32_t context,
+                                         uint64_t context,
                                          HandleSignalsState* signals_state) {
   MutexLocker locker(&mutex_);
   DCHECK(has_local_producer_no_lock());
@@ -618,7 +618,7 @@ HandleSignalsState DataPipe::ConsumerGetHandleSignalsState() {
 
 MojoResult DataPipe::ConsumerAddAwakable(Awakable* awakable,
                                          MojoHandleSignals signals,
-                                         uint32_t context,
+                                         uint64_t context,
                                          HandleSignalsState* signals_state) {
   MutexLocker locker(&mutex_);
   DCHECK(has_local_consumer_no_lock());