Revert of Replace AllAppsTileItemView with ArrowExpandView

ui/app_list/views/suggestions_container_view.cc

Index: ui/app_list/views/suggestions_container_view.cc
diff --git a/ui/app_list/views/suggestions_container_view.cc b/ui/app_list/views/suggestions_container_view.cc
index fef2d865d1aae1edeb8de95a49a5e69b9dfe2c52..b3d2ca6df5654ab7d78f67450059c610fdbe79e1 100644
--- a/ui/app_list/views/suggestions_container_view.cc
+++ b/ui/app_list/views/suggestions_container_view.cc
@@ -20,6 +20,7 @@
 constexpr int kTileSpacing = 7;
 constexpr int kNumTilesCols = 5;
 constexpr int kTilesHorizontalMarginLeft = 145;
+constexpr int kCenterColumnOfStartPageAppGrid = 3;
 
 }  // namespace
 
@@ -147,14 +148,21 @@
     search_result_tile_views_.emplace_back(tile_item);
   }
 
-  if (all_apps_button_ && !is_fullscreen_app_list_enabled_) {
+  if (all_apps_button_)
     all_apps_button_->UpdateIcon();
-
+  if (is_fullscreen_app_list_enabled_) {
+    // Also add a special "all apps" button to the middle of the next row of the
+    // container.
+    tiles_layout_manager->StartRow(0, 0);
+    tiles_layout_manager->SkipColumns(kCenterColumnOfStartPageAppGrid);
+  } else {
     // Also add a special "all apps" button to the end of the next row of the
     // container.
     if (i % kNumTilesCols == 0)
       tiles_layout_manager->StartRow(0, 0);
+  }
 
+  if (all_apps_button_) {
     tiles_layout_manager->AddView(all_apps_button_);
     AddChildView(all_apps_button_);
   }