[gtk] (2 commits) ...Merge branch 'expander-add-like-bin' into 'master'

From: Timm Bäder <baedert src gnome org>
To: commits-list gnome org
Cc:
Subject: [gtk] (2 commits) ...Merge branch 'expander-add-like-bin' into 'master'
Date: Wed, 7 Mar 2018 19:10:29 +0000 (UTC)

Summary of changes:

  a207ab6... expander: Check for an existing child when adding
  6cc824a... Merge branch 'expander-add-like-bin' into 'master'