Revert "Reland "ProGuard: Move -checkdiscard for Log.* into @RemovableInRelease annotation""

This reverts commit 885aa0205473882798718ff3951146620bcd3e24.

Reason for revert: Builders are failing again
Bug: 987226

Original change's description:
> Reland "ProGuard: Move -checkdiscard for Log.* into @RemovableInRelease annotation"
> 
> Was reverted in: 54f75614d20f23f5ff5da505343f28a82323d654.
> 
> Reason for reland: Includes fix for downstream targets.
> 
> Change-Id: I2a5f77cdbd40934ae206dd91b2e12e7b5e6553e1
> Bug: 986693, 986693
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1715004
> Reviewed-by: Sam Maier <smaier@chromium.org>
> Commit-Queue: Andrew Grieve <agrieve@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#680307}

TBR=agrieve@chromium.org,smaier@chromium.org

Change-Id: I210a6fde9d3a37b8e2ea0f7766a127fd95e8616c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 986693
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1715492
Reviewed-by: Rayan Kanso <rayankans@chromium.org>
Commit-Queue: Rayan Kanso <rayankans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#680392}