[Cast Streaming] Lower default playout delay to 200ms

This patch lowers the default playout delay for Cast Streaming
from 400 to 200 milliseconds, on all platforms except ChromeOS.

Bug: b/297389054
Change-Id: Ibb50fcfeb57a9b4cced757147a8efadf52582e4d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5338722


Commit-Queue: Jordan Bayles <jophba@chromium.org>
Reviewed-by: Mark Foltz <mfoltz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1271860}