Add support for KEYCODE_LANGUAGE_SWITCH to switch keyboard layout

Test: manual
Bug: 274096186
Change-Id: I733025e0fc67db71dfe12da54ecfeb6bb563d405

services/core/java/com/android/server/policy/PhoneWindowManager.java

@@ -3183,6 +3183,13 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     }
                 }
                 break;
+            case KeyEvent.KEYCODE_LANGUAGE_SWITCH:
+                if (down && repeatCount == 0) {
+                    int direction = (metaState & KeyEvent.META_SHIFT_MASK) != 0 ? -1 : 1;
+                    sendSwitchKeyboardLayout(event, direction);
+                    return key_consumed;
+                }
+                break;
             case KeyEvent.KEYCODE_SPACE:
                 // Handle keyboard layout switching. (META + SPACE)
                 if ((metaState & KeyEvent.META_META_MASK) == 0) {