Remove mstensho@opera.com as core and core/layout OWNER.

I'm leaving Opera Software today.

TBR=eae@chromium.org
NOTRY=true

Change-Id: Id9e11f73d3a3cbc0f2a772f93945cff21e742933
Reviewed-on: https://chromium-review.googlesource.com/727981Reviewed-by: Morten Stenshorne <mstensho@opera.com>
Commit-Queue: Morten Stenshorne <mstensho@opera.com>
Cr-Commit-Position: refs/heads/master@{#510032}

third_party/WebKit/Source/core/OWNERS

@@ -43,7 +43,6 @@ kojii@chromium.org
 kouhei@chromium.org
 meade@chromium.org
 mkwst@chromium.org
-mstensho@opera.com
 ojan@chromium.org
 # pdr reviews many svg and text autosizing patches.
 pdr@chromium.org

third_party/WebKit/Source/core/layout/OWNERS

@@ -3,7 +3,6 @@ chrishtr@chromium.org
 eae@chromium.org
 fmalita@chromium.org
 fs@opera.com
-mstensho@opera.com
 pdr@chromium.org
 schenney@chromium.org
 skobes@chromium.org