I unintentionally enabled BackgroundResourceFetch feature in
https://crrev.com/c/4956763.
This CL disables this feature by default.

(cherry picked from commit 4d85ec34745f3069b5a1310fecc1bec05386c608)

Bug: 40244488
Change-Id: Icfa3bb879134d8aa7d5e15419ecc7e4c573d5851
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5379631
Commit-Queue: Tsuyoshi Horo <horo@chromium.org>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1274731}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5386709
Commit-Queue: Kouhei Ueno <kouhei@chromium.org>
Auto-Submit: Tsuyoshi Horo <horo@chromium.org>
Cr-Commit-Position: refs/branch-heads/6367@{#181}
Cr-Branched-From: d158c6dc6e3604e6f899041972edf26087a49740-refs/heads/main@{#1274542}