Applied a new fallback color for DarkMode

Signed-off-by: Kilian Périsset <kilian.perisset@infomaniak.com>

src/main/java/com/owncloud/android/ui/activity/DrawerActivity.java

@@ -709,10 +709,12 @@ public abstract class DrawerActivity extends ToolbarActivity
             for (int i = 0; i < mNavigationView.getMenu().size(); i++) {
                 MenuItem menuItem = mNavigationView.getMenu().getItem(i);
                 if (menuItem.getIcon() != null) {
+                    // For the others item
                     if (menuItem != currentItem) {
                         ThemeUtils.tintDrawable(menuItem.getIcon(), drawerColor);
                         ThemeUtils.tintMenuItemText(menuItem, drawerColor);
                     } else {
+                        // For the selected item
                         ThemeUtils.tintDrawable(currentItem.getIcon(), activeColor);
                         ThemeUtils.tintMenuItemText(currentItem, activeColor);
                     }

src/main/res/values-night/colors.xml

@@ -42,6 +42,7 @@
     <color name="switch_thumb_color_unchecked">#2a2a2a</color>
     <color name="switch_track_color_unchecked">#B3FFFFFF</color>
     <color name="drawer_active_item_background">@color/white</color>
+    <color name="element_fallback_color">#EDEDED</color>
 
     <!-- App bar -->
     <color name="appbar">#1E1E1E</color>