study_filtering.cc logs are missing in release

[btlechowski]

Follow up to #14613

The test plan from brave/brave-core#8216 requires to Verify in logs that study loaded correctly with [10210:775:0313/084147.162484:VERBOSE1:study_filtering.cc(346)] Kept study AdvertiserSplitTestingStudy.
The log message is never shown.

Steps to Reproduce

1. Follow Notification ad - GroupA from https://github.com/brave/internal/issues/762

Actual result:

study_filtering.cc logs are missing

Expected result:

study_filtering.cc logs are present
Example from test plan brave/brave-core#8216

[10210:775:0313/084147.162484:VERBOSE1:study_filtering.cc(346)] Kept study AdvertiserSplitTestingStudy

Reproduces how often:

Easily reproduced

Brave version (brave://version info)

Brave	1.23.63 Chromium: 89.0.4389.114 (Official Build) beta (64-bit)
Revision	1ea76e193b4fadb723bfea2a19a66c93a1bc0ca6-refs/branch-heads/4389@{#1616}
OS	Ubuntu 18.04 LTS

cc @moritzhaller @tmancey @jsecretan @brave/legacy_qa

[moritzhaller]

I've noticed these logs are not showing on release builds. Maybe @iefremov can help?

[iefremov]

yeah this is expected, since those are debug logs

[tmancey]

Closing issue as working as expected