Stringify bools consistently

This changes instances of `b ? "true" : "false"` to use
`base::ToString(b)` instead, for consistency.

This change applies to the following directories:
media

This CL was uploaded by git cl split.

Bug: 335797528
Change-Id: Ic4ec9b542011f78d1ecb53845425f9bafb3c7a94
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6327586
Reviewed-by: Ted (Chromium) Meyer <tmathmeyer@chromium.org>
Auto-Submit: Devon Loehr <dloehr@google.com>
Commit-Queue: Ted (Chromium) Meyer <tmathmeyer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1428500}