[react-native] Add AccessibilityAction name definition (#38703)

types/react-native/index.d.ts

@@ -24,6 +24,7 @@
 //                 Theo Henry de Villeneuve <https://github.com/theohdv>
 //                 Eli White <https://github.com/TheSavior>
 //                 Romain Faust <https://github.com/romain-faust>
+//                 Be Birchall <https://github.com/bebebebebe>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.8
 
@@ -2009,10 +2010,39 @@ export interface AccessibilityProps extends AccessibilityPropsAndroid, Accessibi
 }
 
 export type AccessibilityActionInfo = Readonly<{
-    name: string;
+    name: AccessibilityActionName;
     label?: string;
 }>;
 
+export type AccessibilityActionName =
+    /**
+     * Generated when a screen reader user double taps the component.
+     */
+    | 'activate'
+    /**
+     * Gererated when a screen reader user increments an adjustable component.
+     */
+    | 'increment'
+    /**
+     * Gererated when a screen reader user decrements an adjustable component.
+     */
+    | 'decrement'
+    /**
+     * Generated when a TalkBack user places accessibility focus on the component and double taps and holds one finger on the screen.
+     * @platform android
+     */
+    | 'longpress'
+    /**
+     * Generated when a VoiceOver user places focus on or inside the component and double taps with two fingers.
+     * @platform ios
+     * */
+    | 'magicTap'
+    /**
+     * Generated when a VoiceOver user places focus on or inside the component and performs a two finger scrub gesture (left, right, left).
+     * @platform ios
+     * */
+    | 'escape';
+
 export type AccessibilityActionEvent = NativeSyntheticEvent<
     Readonly<{
         actionName: string;