[macos] add NSWindow.hasShadow support (#1637)

* [macos] add NSWindow.hasShadow

* change log

* cargo fmt

* Update CHANGELOG.md

* Update src/platform_impl/macos/window.rs

* Update src/platform/macos.rs

* set_has_shadow() with cuter format

* adjust code

* cargo fmt

* changelog

src/platform/macos.rs

@@ -56,6 +56,12 @@ pub trait WindowExtMacOS {
     /// And allows the user to have a fullscreen window without using another
     /// space or taking control over the entire monitor.
     fn set_simple_fullscreen(&self, fullscreen: bool) -> bool;
+
+    /// Returns whether or not the window has shadow.
+    fn has_shadow(&self) -> bool;
+
+    /// Sets whether or not the window has shadow.
+    fn set_has_shadow(&self, has_shadow: bool);
 }
 
 impl WindowExtMacOS for Window {
@@ -83,6 +89,16 @@ impl WindowExtMacOS for Window {
     fn set_simple_fullscreen(&self, fullscreen: bool) -> bool {
         self.window.set_simple_fullscreen(fullscreen)
     }
+
+    #[inline]
+    fn has_shadow(&self) -> bool {
+        self.window.has_shadow()
+    }
+
+    #[inline]
+    fn set_has_shadow(&self, has_shadow: bool) {
+        self.window.set_has_shadow(has_shadow)
+    }
 }
 
 /// Corresponds to `NSApplicationActivationPolicy`.
@@ -131,6 +147,7 @@ pub trait WindowBuilderExtMacOS {
     /// Build window with `resizeIncrements` property. Values must not be 0.
     fn with_resize_increments(self, increments: LogicalSize<f64>) -> WindowBuilder;
     fn with_disallow_hidpi(self, disallow_hidpi: bool) -> WindowBuilder;
+    fn with_has_shadow(self, has_shadow: bool) -> WindowBuilder;
 }
 
 impl WindowBuilderExtMacOS for WindowBuilder {
@@ -190,6 +207,12 @@ impl WindowBuilderExtMacOS for WindowBuilder {
         self.platform_specific.disallow_hidpi = disallow_hidpi;
         self
     }
+
+    #[inline]
+    fn with_has_shadow(mut self, has_shadow: bool) -> WindowBuilder {
+        self.platform_specific.has_shadow = has_shadow;
+        self
+    }
 }
 
 /// Additional methods on `MonitorHandle` that are specific to MacOS.