[PM-2320] Improve Android block Auto-fill URIs (#2616)

* PM-2320 Added new view for block autofill URIs on Android

* PM-2320 Fix formatting

* PM-2320 Improved validations on block autofill uris

* PM-2320 Improved autofill block uris placeholder colors on different themes

src/App/Pages/Settings/BlockAutofillUrisPage.xaml.cs

@@ -0,0 +1,44 @@
+using System.Threading.Tasks;
+using Bit.App.Styles;
+using Bit.App.Utilities;
+using Bit.Core.Utilities;
+using Xamarin.Essentials;
+using Xamarin.Forms;
+
+namespace Bit.App.Pages
+{
+    public partial class BlockAutofillUrisPage : BaseContentPage, IThemeDirtablePage
+    {
+        private readonly BlockAutofillUrisPageViewModel _vm;
+
+        public BlockAutofillUrisPage()
+        {
+            InitializeComponent();
+
+            _vm = BindingContext as BlockAutofillUrisPageViewModel;
+            _vm.Page = this;
+        }
+
+        protected override void OnAppearing()
+        {
+            base.OnAppearing();
+
+            _vm.InitAsync().FireAndForget(_ => Navigation.PopAsync());
+
+            UpdatePlaceholder();
+        }
+
+        public override async Task UpdateOnThemeChanged()
+        {
+            await base.UpdateOnThemeChanged();
+
+            UpdatePlaceholder();
+        }
+
+        private void UpdatePlaceholder()
+        {
+            MainThread.BeginInvokeOnMainThread(() =>
+                _emptyUrisPlaceholder.Source = ImageSource.FromFile(ThemeManager.UsingLightTheme ? "empty_uris_placeholder" : "empty_uris_placeholder_dark"));
+        }
+    }
+}