Round corners of workspaces in multitasking view

data/gala.css

@@ -46,6 +46,7 @@
 }
 
 .workspace.decoration {
+    border-radius: 6px;
     box-shadow:
         0 0 0 1px alpha(#000, 0.2),
         0 8px 10px 1px alpha(#000, 0.14),

src/Background/BackgroundManager.vala

@@ -117,14 +117,22 @@ public class Gala.BackgroundManager : Meta.BackgroundGroup {
         unowned var content = (Meta.BackgroundContent) background_actor.content;
         content.background = background.background;
 
+        var monitor = display.get_monitor_geometry (monitor_index);
+        var rect = Graphene.Rect () {
+            origin = {monitor.x, monitor.y},
+            size = {monitor.width, monitor.height},
+        };
+
+        content.set_rounded_clip_bounds (rect);
+        content.rounded_clip_radius = Utils.scale_to_int (6, display.get_monitor_scale (monitor_index));
+
         if (background_source.should_dim) {
             content.vignette = true;
             content.brightness = DIM_OPACITY;
         }
 
         insert_child_below (background_actor, null);
 
-        var monitor = display.get_monitor_geometry (monitor_index);
         background_actor.set_size (monitor.width, monitor.height);
 
         ulong changed_handler = 0;

src/Widgets/WorkspaceClone.vala

@@ -63,7 +63,7 @@ namespace Gala {
             var ctx = cached_context;
 
             ctx.set_source_rgba (255, 255, 255, 255);
-            ctx.rectangle (0, 0, (int) width, (int) height);
+            Drawing.Utilities.cairo_rounded_rectangle (ctx, 0, 0, width, height, 9);
             ctx.set_operator (Cairo.Operator.SOURCE);
             ctx.stroke ();
             ctx.restore ();