[libgweather] weather: Guard against segfault

[Florian Müllner <fmuellner src gnome org>]

commit 61e09326f153f7eed78da21c70a5a97fd9be0390
Author: Florian Müllner <fmuellner gnome org>
Date:   Sun Mar 19 17:25:11 2017 +0100

    weather: Guard against segfault
    
    When GWeatherInfo:location is set to %NULL, the default location will
    be used. Currently the code assumes that this fallback can always be
    resolved, however find_by_station_code() may return %NULL, resulting
    in a segfault.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=780278

 libgweather/gweather-weather.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/libgweather/gweather-weather.c b/libgweather/gweather-weather.c
index 87fb8fd..20b8c58 100644
--- a/libgweather/gweather-weather.c
+++ b/libgweather/gweather-weather.c
@@ -2002,7 +2002,6 @@ gweather_info_set_location_internal (GWeatherInfo     *info,
 
     if (priv->glocation)
        gweather_location_unref (priv->glocation);
-    _weather_location_free (&priv->location);
 
     priv->glocation = location;
 
@@ -2023,8 +2022,12 @@ gweather_info_set_location_internal (GWeatherInfo     *info,
        priv->glocation = gweather_location_find_by_station_code (world, station_code);
     }
 
-    _gweather_location_update_weather_location (priv->glocation,
-                                               &priv->location);
+    if (priv->glocation) {
+        _weather_location_free (&priv->location);
+        _gweather_location_update_weather_location (priv->glocation,
+                                                   &priv->location);
+    }
+
     if (name) {
        g_free (priv->location.name);
        priv->location.name = g_strdup (name);