Migrate CreateDecryptor|CreateCdmProxy to new Mojo types in InterfaceFactory

Applies pending_receiver to CreateDecryptor and CreateCdmProxy
in InterfaceFactory interface.

Major changes are as below,

  - Convert InterfaceRequest to mojo::PendingReceiver<Interface>
  - Convert mojo::StrongBindingSet to mojo::UniqueReceiverSet
  - Convert InterfacePtr to mojo::Remote.

Bug: 955171
Change-Id: I9ba94da2ccb4ff82109b30db7a794483d30dd39c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1828674
Reviewed-by: Olga Sharonova <olka@chromium.org>
Reviewed-by: John Rummell <jrummell@chromium.org>
Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Gyuyoung Kim <gyuyoung@igalia.com>
Cr-Commit-Position: refs/heads/master@{#701383}
10 files changed