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 4ae663a9b1d3a1b8853b9f625e1a9cce9070f9eb..9b7e8d5bc08eb22c84bb04dc575e8ee855f99450 100644
--- a/gpu/ipc/in_process_command_buffer.cc
+++ b/gpu/ipc/in_process_command_buffer.cc
@@ -1018,9 +1018,11 @@ 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)