Remove unnecessary runtime_enabled_features.h includes

Bug: 40318405
Change-Id: Iccbddc43799e7b22503cf896a346bc29f18c99c9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5553003


Auto-Submit: Kent Tamura <tkent@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1304291}