[Direct Receiver] Viz Compositor Direct Receiver for FrameSinkManager

By making the primary interface from a group of associated interfaces
direct, all the interfaces involved become Direct Receivers.

This CL converts the primary interface (FrameSinkManager) to a direct
receiver, allowing RCFSI, DisplayPrivate (and many other interfaces) to
benefit from reduced latency by eliminating the I/O thread hop.

NOTE: This surfaces a subtle behaviour of Direct Receiver. Every pending
receiver passed through FSM will receive I/O on the VizCompositor
thread. This is fine as long as those receivers are bound to
VizCompositor, which seems to be the case here. The bug contains more
details.

Bug: 430256405
Change-Id: Icd60262483428f24d4f01616f2ba407eddef3a63
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6655377
Reviewed-by: Jonathan Ross <jonross@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Nafis Abedin <nafisabedin@google.com>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1504686}