ANativeWindow_fromSurface: Use acquire not incStrong

When we call incStrong like this, it won't work if the
caller of ANativeWindow_fromSurface later calls
ANativeWindow_release and so we leak the reference indefinitely.
We change to call acquire so that the caller can call release.

Bug: 186190571
Test: Existing tests pass
Change-Id: I647a856923c891da2d305471f5ff84103d1f9ed5
diff --git a/native/android/native_window_jni.cpp b/native/android/native_window_jni.cpp
index 859c550..901b4de 100644
--- a/native/android/native_window_jni.cpp
+++ b/native/android/native_window_jni.cpp
@@ -30,7 +30,7 @@
 ANativeWindow* ANativeWindow_fromSurface(JNIEnv* env, jobject surface) {
     sp<ANativeWindow> win = android_view_Surface_getNativeWindow(env, surface);
     if (win != NULL) {
-        win->incStrong((void*)ANativeWindow_fromSurface);
+        ANativeWindow_acquire(win.get());
     }
     return win.get();
 }