CrOS: Update AppListFolder to respect 8 in margin on devices with narrow screens.

Bug: 984365
Change-Id: I06da9bc0f3498696133b13dd1c724eb6ef2f1beb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1827743Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#701183}

ash/app_list/views/app_list_folder_view.cc

@@ -610,10 +610,10 @@ void AppListFolderView::UpdatePreferredBounds() {
         0, GetAppListConfig().search_box_fullscreen_top_padding(), 0, 0);
   }
   // Avoid overlap with the search box widget.
-  container_bounds.Inset(0,
+  container_bounds.Inset(8,
                          search_box::kSearchBoxPreferredHeight +
                              SearchBoxView::GetFocusRingSpacing(),
-                         0, 0);
+                         8, 0);
 
   preferred_bounds_.AdjustToFit(container_bounds);