Add retained paints and shared text selection

examples/message_list.rs

@@ -27,11 +27,11 @@ fn row_image(i: usize) -> image::DynamicImage {
 
 fn build_row<Rsc: UiRsc + 'static>(rsc: &mut Rsc, i: usize) -> StrongWidget {
     let tint = if i.is_multiple_of(2) {
-        Color::rgb(120, 130, 170)
+        Srgba8::rgb(120, 130, 170)
     } else {
-        Color::rgb(70, 80, 140)
+        Srgba8::rgb(70, 80, 140)
     };
-    let text_color = Color::BLACK;
+    let text_color = PaintId::BLACK;
     if i.is_multiple_of(IMAGE_EVERY) {
         let text = wtext(row_text(i))
             .wrap(true)
@@ -77,7 +77,7 @@ impl DefaultAppState for State {
         let root = list
             .scrollable()
             .masked()
-            .background(rect(Color::WHITE))
+            .background(rect(PaintId::WHITE))
             .add_strong(rsc);
         ui_state.set_root(root.any());