fix: don't use deprecated currentlyFocusedField (facebook#8365)

Co-authored-by: Satyajit Sahoo <[email protected]>

Author: kangyunu

packages/stack/src/views/KeyboardManager.tsx

@@ -35,7 +35,11 @@ export default class KeyboardManager extends React.Component<Props> {
 
     this.clearKeyboardTimeout();
 
-    const input = TextInput.State.currentlyFocusedField();
+    // @ts-ignore
+    const input = TextInput.State.currentlyFocusedInput
+      ? // @ts-ignore
+        TextInput.State.currentlyFocusedInput()
+      : TextInput.State.currentlyFocusedField();
 
     // When a page change begins, blur the currently focused input
     TextInput.State.blurTextInput(input);