Appearance.setColorScheme support (revisited) (#36122)

Summary:
Both Android and iOS allow you to set application specific user interface style, which is useful for applications that support both light and dark mode.

With the newly added `Appearance.setColorScheme`, you can natively manage the application's user interface style rather than keeping that preference in JavaScript. The benefit is that native dialogs like alert, keyboard, action sheets and more will also be affected by this change.

Implemented using Android X [AppCompatDelegate.setDefaultNightMode](https://developer.android.com/reference/androidx/appcompat/app/AppCompatDelegate#setDefaultNightMode(int)) and iOS 13+ [overrideUserInterfaceStyle](https://developer.apple.com/documentation/uikit/uiview/3238086-overrideuserinterfacestyle?language=objc)

```tsx
// Lets assume a given device is set to **dark** mode.

Appearance.getColorScheme(); // `dark`

// Set the app's user interface to `light`
Appearance.setColorScheme('light');

Appearance.getColorScheme(); // `light`

// Set the app's user interface to `unspecified`
Appearance.setColorScheme(null);

Appearance.getColorScheme() // `dark`
 ```

## Changelog

[GENERAL] [ADDED] - Added `setColorScheme` to `Appearance` module

Pull Request resolved: https://github.com/facebook/react-native/pull/36122

Test Plan:
Added a RNTester for the feature in the Appearance section.

Three buttons for toggling all set of modes.

Reviewed By: lunaleaps

Differential Revision: D43331405

Pulled By: NickGerleman

fbshipit-source-id: 3b15f1ed0626d1ad7a8266ec026e903cd3ec46aa

ReactAndroid/src/main/java/com/facebook/react/modules/appearance/AppearanceModule.java

@@ -11,6 +11,7 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.res.Configuration;
 import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatDelegate;
 import com.facebook.fbreact.specs.NativeAppearanceSpec;
 import com.facebook.react.bridge.Arguments;
 import com.facebook.react.bridge.ReactApplicationContext;
@@ -65,6 +66,17 @@ public class AppearanceModule extends NativeAppearanceSpec {
     return "light";
   }
 
+  @Override
+  public void setColorScheme(String style) {
+    if (style.equals("dark")) {
+      AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
+    } else if (style.equals("light")) {
+      AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
+    } else if (style.equals("unspecified")) {
+      AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_FOLLOW_SYSTEM);
+    }
+  }
+
   @Override
   public String getColorScheme() {
     // Attempt to use the Activity context first in order to get the most up to date

ReactAndroid/src/main/java/com/facebook/react/modules/appearance/BUCK

@@ -14,6 +14,7 @@ rn_android_library(
     deps = [
         react_native_dep("third-party/java/jsr-305:jsr-305"),
         react_native_dep("third-party/android/androidx:annotation"),
+        react_native_dep("third-party/android/androidx:appcompat"),
         react_native_target("java/com/facebook/react/bridge:bridge"),
         react_native_target("java/com/facebook/react/common:common"),
         react_native_target("java/com/facebook/react/module/annotations:annotations"),

ReactAndroid/src/main/java/com/facebook/react/shell/BUCK

@@ -15,6 +15,7 @@ rn_android_library(
         react_native_dep("libraries/fresco/fresco-react-native:imagepipeline"),
         react_native_dep("libraries/soloader/java/com/facebook/soloader:soloader"),
         react_native_dep("third-party/android/androidx:annotation"),
+        react_native_dep("third-party/android/androidx:appcompat"),
         react_native_dep("third-party/android/androidx:core"),
         react_native_dep("third-party/android/androidx:fragment"),
         react_native_dep("third-party/android/androidx:legacy-support-core-utils"),