[gnome-software] Release version 3.27.4

[Kalev Lember <klember src gnome org>]

commit f895348886b1da015aecd6f29ae6e861df1680e4
Author: Kalev Lember <klember redhat com>
Date:   Mon Jan 8 21:06:56 2018 +0100

    Release version 3.27.4

 NEWS                                           |   17 +++++++++++++++++
 data/appdata/org.gnome.Software.appdata.xml.in |   19 +++++++++++++++++++
 2 files changed, 36 insertions(+), 0 deletions(-)
---
diff --git a/NEWS b/NEWS
index 9dbd3ff..d6cdf47 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,20 @@
+Version 3.27.4
+~~~~~~~~~~~~~~
+Released: 2018-01-08
+
+This is an unstable release in the 3.27 development series, with the following
+improvements:
+ * Add missing locking to gs_plugin_cache_remove(), fixing a possible crash
+ * Fix various memory leaks spotted by valgrind
+ * Fix a possible crash triggered by the fwupd plugin
+ * Do not emit critical warnings when reviewing OS Updates
+ * fwupd: Use the custom user-agent when downloading firmware
+ * overview page: Fix a crash when we have no featured apps
+ * packagekit: Implement repository enabling
+ * Fix hover CSS for "unknown" and "nonfree" license buttons
+
+This release also updates translations.
+
 Version 3.27.3
 ~~~~~~~~~~~~~~
 Released: 2017-11-13
diff --git a/data/appdata/org.gnome.Software.appdata.xml.in b/data/appdata/org.gnome.Software.appdata.xml.in
index 3fe1b44..0bac4d2 100644
--- a/data/appdata/org.gnome.Software.appdata.xml.in
+++ b/data/appdata/org.gnome.Software.appdata.xml.in
@@ -46,6 +46,25 @@
    Validate with `appstream-util validate *.appdata.xml`
   -->
   <releases>
+    <release date="2018-01-08" version="3.27.4">
+      <description>
+        <p>
+          This is an unstable release in the 3.27 development series,
+          with the following improvements:
+        </p>
+        <ul>
+          <li>Add missing locking to gs_plugin_cache_remove(), fixing a possible crash</li>
+          <li>Fix various memory leaks spotted by valgrind</li>
+          <li>Fix a possible crash triggered by the fwupd plugin</li>
+          <li>Do not emit critical warnings when reviewing OS Updates</li>
+          <li>fwupd: Use the custom user-agent when downloading firmware</li>
+          <li>overview page: Fix a crash when we have no featured apps</li>
+          <li>packagekit: Implement repository enabling</li>
+          <li>Fix hover CSS for "unknown" and "nonfree" license buttons</li>
+        </ul>
+        <p>This release also updates translations.</p>
+      </description>
+    </release>
     <release date="2017-11-13" version="3.27.3">
       <description>
         <p>