Implement From traits for Style in canvas

graphics/src/widget/canvas/style.rs

@@ -9,3 +9,15 @@ pub enum Style {
     /// A [`Gradient`] color.
     Gradient(Gradient),
 }
+
+impl From<Color> for Style {
+    fn from(color: Color) -> Self {
+        Self::Solid(color)
+    }
+}
+
+impl From<Gradient> for Style {
+    fn from(gradient: Gradient) -> Self {
+        Self::Gradient(gradient)
+    }
+}