Use ScopedLocalRef in InputEvent jni function

This CL updates some jni functions that manipulate Key and Motion events
to use ScopedLocalRef instead of plain jobject for better life-cycle
tracking.

Test: presubmit
Bug: 324375527
Change-Id: I154b0606d3c0912f0df7a890faf7246b575863f5
diff --git a/native/android/input.cpp b/native/android/input.cpp
index 4708e69..53699bc 100644
--- a/native/android/input.cpp
+++ b/native/android/input.cpp
@@ -321,11 +321,13 @@
         case AINPUT_EVENT_TYPE_MOTION:
             return android::android_view_MotionEvent_obtainAsCopy(env,
                                                                   static_cast<const MotionEvent&>(
-                                                                          *aInputEvent));
+                                                                          *aInputEvent))
+                    .release();
         case AINPUT_EVENT_TYPE_KEY:
             return android::android_view_KeyEvent_obtainAsCopy(env,
                                                                static_cast<const KeyEvent&>(
-                                                                       *aInputEvent));
+                                                                       *aInputEvent))
+                    .release();
         default:
             LOG_ALWAYS_FATAL("Unexpected event type %d in AInputEvent_toJava.", eventType);
     }