base/allocator: Remove unused feature as it is enabled by default.

Periodic reclaim is enabled by default, remove the feature. As a consequence,
remove the no-op DeprecatedReclaim() call, and its call site.

Bug: 942512
Change-Id: I916dfa1f1aee17bc3f3ac8a1de16ea2c1d987b0d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1782698
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#693060}
6 files changed