Merge pull request #473 from telerik/Aleks/calendar-uwp-background-topHeader

Apply calendar background to the top header of the multiday view.

Author: APopatanasov

Controls/Input/Input.UWP/Calendar/View/Layers/XamlMultiDayViewLayer.cs

@@ -666,6 +666,7 @@ internal void ArrangeVisualElement()
             }
 
             this.UpdatePanelsBackground(calendar.MultiDayViewSettings.TimelineBackground);
+            this.UpdateTopHeaderBackground();
         }
 
         internal void UpdatePanelsBackground(Brush background)
@@ -1224,5 +1225,19 @@ private void ApplyTimeRulerStyle(object item, FrameworkElement container)
                 }
             }
         }
+
+        private void UpdateTopHeaderBackground()
+        {
+            Brush defaultCalendarBrush = this.Owner.Background ?? MultiDayViewSettings.DefaultBackground;
+            if (this.topHeader.Background != defaultCalendarBrush)
+            {
+                this.topHeader.Background = defaultCalendarBrush;
+            }
+
+            if (this.topLeftHeaderPanel.Background != defaultCalendarBrush)
+            {
+                this.topLeftHeaderPanel.Background = defaultCalendarBrush;
+            }
+        }
     }
 }