GitLab

This reverts commit a9ed1fd3.

Reason for revert: Speculative revert since two WebRTC bots started failing reliably after this CL.
If the revert does not fix the bots (which I think is likely), we will reland it.

Original change's description:
> [NTP] Clear attribution on the existing tab when apply a theme
> 
> Now we will clear the attribution also on the existing tab when a theme
> is applied.
> 
> Bug: 875519
> Change-Id: I65e8a0dc1ed3492c512cabcf1a2d3f0e6f2e64f7
> Reviewed-on: https://chromium-review.googlesource.com/1181684
> Commit-Queue: Weilun Shi <sweilun@chromium.org>
> Reviewed-by: Kristi Park <kristipark@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#584964}

TBR=kristipark@chromium.org,ramyan@chromium.org,kmilka@chromium.org,sweilun@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 875519
Change-Id: I20ff372903d2abee0620d42e9cff18777515ac65
Reviewed-on: https://chromium-review.googlesource.com/1186762Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Commit-Queue: Guido Urdaneta <guidou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585499}