The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c9fc21ef0c181062a010a94b5b6b74d213fe5307

commit c9fc21ef0c181062a010a94b5b6b74d213fe5307
Author: Dave Tapuska <dtapuska@chromium.org>
Date: Wed Oct 31 16:17:29 2018

Move optional to dictionary instead of on transfer.

Mozilla has requested changes to the IDL and either format is identical
for Chrome (after we've shipped). They weren't when it was optional.

BUG= 899734 

Change-Id: I85dc7e27c4dc77f5f6443e6ba212f4835ba30e77
Reviewed-on: https://chromium-review.googlesource.com/c/1304615
Reviewed-by: David Bokan <bokan@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604280}
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/core/frame/window.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/core/messaging/message_port.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/core/workers/dedicated_worker_global_scope.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/core/workers/worker.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/modules/service_worker/client.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/modules/service_worker/service_worker.idl
[modify] https://crrev.com/c9fc21ef0c181062a010a94b5b6b74d213fe5307/third_party/blink/renderer/platform/runtime_enabled_features.json5