Enforce use_key_in_widget_constructors and file_names lints (#913)

* Start enforcing use_key_in_widget_constructors and file_names lints

* dart format

* analysis fixes

* analysis fixes, pt2

* analysis fixes, part 3

* Revert platform_design (test failure)

* More reverts

* Notate why we aren't enforcing a lint

experimental/web_dashboard/lib/src/pages/dashboard.dart

@@ -10,6 +10,8 @@ import '../app.dart';
 import '../widgets/category_chart.dart';
 
 class DashboardPage extends StatelessWidget {
+  const DashboardPage({Key key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     var appState = Provider.of<AppState>(context);
@@ -41,7 +43,7 @@ class DashboardPage extends StatelessWidget {
 class Dashboard extends StatelessWidget {
   final List<Category> categories;
 
-  const Dashboard(this.categories);
+  const Dashboard(this.categories, {Key key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

experimental/web_dashboard/lib/src/pages/entries.dart

@@ -12,6 +12,8 @@ import '../widgets/categories_dropdown.dart';
 import '../widgets/dialogs.dart';
 
 class EntriesPage extends StatefulWidget {
+  const EntriesPage({Key key}) : super(key: key);
+
   @override
   _EntriesPageState createState() => _EntriesPageState();
 }
@@ -100,7 +102,8 @@ class EntryTile extends StatelessWidget {
   const EntryTile({
     this.category,
     this.entry,
-  });
+    Key key,
+  }) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

experimental/web_dashboard/lib/src/pages/home.dart

@@ -14,7 +14,8 @@ class HomePage extends StatefulWidget {
 
   const HomePage({
     @required this.onSignOut,
-  });
+    Key key,
+  }) : super(key: key);
 
   @override
   _HomePageState createState() => _HomePageState();
@@ -70,7 +71,7 @@ class _HomePageState extends State<HomePage> {
     if (_pageIndex == 0) {
       showDialog<NewCategoryDialog>(
         context: context,
-        builder: (context) => NewCategoryDialog(),
+        builder: (context) => const NewCategoryDialog(),
       );
       return;
     }
@@ -78,7 +79,7 @@ class _HomePageState extends State<HomePage> {
     if (_pageIndex == 1) {
       showDialog<NewEntryDialog>(
         context: context,
-        builder: (context) => NewEntryDialog(),
+        builder: (context) => const NewEntryDialog(),
       );
       return;
     }
@@ -115,11 +116,11 @@ class _HomePageState extends State<HomePage> {
 
   static Widget _pageAtIndex(int index) {
     if (index == 0) {
-      return DashboardPage();
+      return const DashboardPage();
     }
 
     if (index == 1) {
-      return EntriesPage();
+      return const EntriesPage();
     }
 
     return const Center(child: Text('Settings page'));

experimental/web_dashboard/lib/src/pages/sign_in.dart

@@ -13,7 +13,8 @@ class SignInPage extends StatelessWidget {
   const SignInPage({
     @required this.auth,
     @required this.onSuccess,
-  });
+    Key key,
+  }) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
@@ -32,7 +33,8 @@ class SignInButton extends StatefulWidget {
   const SignInButton({
     @required this.auth,
     @required this.onSuccess,
-  });
+    Key key,
+  }) : super(key: key);
 
   @override
   _SignInButtonState createState() => _SignInButtonState();