added whitespace to bottom for some screens + increased vertical padding for 'Delete all' button on iOS

lib/ui/archive_page.dart

@@ -52,6 +52,7 @@ class ArchivePage extends StatelessWidget {
       tagPrefix: tagPrefix,
       selectedFiles: _selectedFiles,
       initialFiles: null,
+      footer: SizedBox(height: 32),
     );
     return Scaffold(
       appBar: PreferredSize(

lib/ui/device_folder_page.dart

@@ -37,6 +37,7 @@ class DeviceFolderPage extends StatelessWidget {
           ? _getHeaderWidget()
           : Container(),
       initialFiles: [folder.thumbnail],
+      footer: SizedBox(height: 32),
     );
     return Scaffold(
       appBar: PreferredSize(

lib/ui/location_search_results_page.dart

@@ -39,6 +39,7 @@ class _LocationSearchResultsPageState extends State<LocationSearchResultsPage> {
         child: Gallery(
           tagPrefix: "location_search",
           selectedFiles: _selectedFiles,
+          footer: SizedBox(height: 32),
         ),
       ),
     );

lib/ui/trash_page.dart

@@ -1,3 +1,4 @@
+import 'dart:io';
 import 'dart:ui';
 
 import 'package:flutter/material.dart';
@@ -70,6 +71,7 @@ class _TrashPageState extends State<TrashPage> {
       selectedFiles: widget._selectedFiles,
       header: _headerWidget(),
       initialFiles: null,
+      footer: const SizedBox(height: 32),
     );
 
     return Scaffold(
@@ -152,7 +154,8 @@ class BottomButtonsWidget extends StatelessWidget {
                 decoration: BoxDecoration(
                   color: Color.fromRGBO(255, 101, 101, 0.2),
                 ),
-                padding: EdgeInsets.symmetric(horizontal: 24),
+                padding: EdgeInsets.symmetric(
+                    horizontal: 24, vertical: Platform.isIOS ? 24 : 0),
                 child: Center(
                   child: Text(
                     'Delete All',