Merge "libbinder_ndk: avoid need to allocate heap status" am: 9b1e10db73 am: 2133bd5454 am: 7a07f2fe76 am: 623a229a0c

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/1434715

Change-Id: I223106e580d508b9009e30b0232b51a9ea522206
diff --git a/libs/binder/ndk/include_cpp/android/binder_auto_utils.h b/libs/binder/ndk/include_cpp/android/binder_auto_utils.h
index f59bb75..439b019 100644
--- a/libs/binder/ndk/include_cpp/android/binder_auto_utils.h
+++ b/libs/binder/ndk/include_cpp/android/binder_auto_utils.h
@@ -199,6 +199,9 @@
    public:
     /**
      * Takes ownership of a.
+     *
+     * WARNING: this constructor is only expected to be used when reading a
+     *     status value. Use `ScopedAStatus::ok()` instead.
      */
     explicit ScopedAStatus(AStatus* a = nullptr) : ScopedAResource(a) {}
     ~ScopedAStatus() {}
diff --git a/libs/binder/ndk/status.cpp b/libs/binder/ndk/status.cpp
index 4fd59a2..a8ae441 100644
--- a/libs/binder/ndk/status.cpp
+++ b/libs/binder/ndk/status.cpp
@@ -23,7 +23,8 @@
 using ::android::binder::Status;
 
 AStatus* AStatus_newOk() {
-    return new AStatus();
+    static AStatus status = AStatus();
+    return &status;
 }
 
 AStatus* AStatus_fromExceptionCode(binder_exception_t exception) {
@@ -78,7 +79,9 @@
 }
 
 void AStatus_delete(AStatus* status) {
-    delete status;
+    if (status != AStatus_newOk()) {
+        delete status;
+    }
 }
 
 binder_status_t PruneStatusT(status_t status) {