gpu: Add sync token dependencies to flush metadata.

gpu/ipc/in_process_command_buffer.cc

Index: gpu/ipc/in_process_command_buffer.cc
diff --git a/gpu/ipc/in_process_command_buffer.cc b/gpu/ipc/in_process_command_buffer.cc
index 7db6617e44f7289686f082dd7687ee8bd362a97b..ce88582d11eb9f73c601554715e4009012c4b31f 100644
--- a/gpu/ipc/in_process_command_buffer.cc
+++ b/gpu/ipc/in_process_command_buffer.cc
@@ -981,9 +981,11 @@ void InProcessCommandBuffer::SignalSyncToken(const SyncToken& sync_token,
                  base::Unretained(this), sync_token, WrapCallback(callback)));
 }
 
+void InProcessCommandBuffer::WaitSyncToken(const SyncToken& sync_token) {}
+
 bool InProcessCommandBuffer::CanWaitUnverifiedSyncToken(
-    const SyncToken* sync_token) {
-  return sync_token->namespace_id() == GetNamespaceID();
+    const SyncToken& sync_token) {
+  return sync_token.namespace_id() == GetNamespaceID();
 }
 
 #if defined(OS_WIN)