(css) Improve autocompletion display

UI/WebServerResources/scss/components/chips/chips.scss

@@ -50,6 +50,12 @@ md-chips {
 // Enlarge the default autocompletion menu
 .sg-chips-autocomplete {
   width: (3 * $contact-chip-name-width);
+  @media (max-width: $layout-breakpoint-xs) {
+    // Enlarge the autocompletion menu on small devices to fit the entire screen
+    left: 0;
+    right: 0;
+    width: auto;
+  }
 }
 
 // Adjust avatar size according to chips dimensions

UI/WebServerResources/scss/components/virtualRepeat/virtual-repeat.scss

@@ -1,9 +1,2 @@
 /// virtualRepeater.scss -*- Mode: scss; indent-tabs-mode: nil; basic-offset: 2 -*-
 @import 'extends';
-
-// Override some md styles
-.md-virtual-repeat-container {
-  .md-virtual-repeat-offsetter {
-    right: 0; // no need to keep space for the scrollbar
-  }
-}