dateMenu: Tweak temperature labels

Together with the forecast icon, the temperature label is the most
important information in the weather section. To emphasize it more,
reduce its space requirement by removing the temperature unit, then
make the text bold.

https://gitlab.gnome.org/GNOME/gnome-shell/issues/1143

data/theme/gnome-shell-sass/widgets/_calendar.scss

@@ -222,6 +222,10 @@
     icon-size: $base_icon_size * 2;
   }
 
+  .weather-forecast-temp {
+    font-weight: bold;
+  }
+
   .weather-forecast-time {
     color: darken($fg_color,30%);
     font-feature-settings: "tnum";

js/ui/dateMenu.js

@@ -348,6 +348,8 @@ class WeatherSection extends St.Button {
                 timeOnly: true,
                 ampm: false,
             });
+            const [, tempValue] = fc.get_value_temp(GWeather.TemperatureUnit.DEFAULT);
+            const tempPrefix = tempValue >= 0 ? ' ' : '';
 
             let icon = new St.Icon({
                 style_class: 'weather-forecast-icon',
@@ -357,7 +359,7 @@ class WeatherSection extends St.Button {
             });
             let temp = new St.Label({
                 style_class: 'weather-forecast-temp',
-                text: fc.get_temp_summary(),
+                text: '%s%.0f°'.format(tempPrefix, tempValue),
                 x_align: Clutter.ActorAlign.CENTER,
             });
             let time = new St.Label({