SharedMemory API changes

Hides getFd & getFileDescriptor due to lifecycle concenrs.
Adds ASharedMemory_dupFromJava to allow sharing a shared
memory region between Java & Native as safe as possible.
Mis-use results in an FD leak instead of double-close.

Bug: 64394076
Test: SharedMemory CTS tests
Change-Id: I01a5eb978fc4e99559a79baac75754c32f13bdc4
diff --git a/native/android/libandroid.map.txt b/native/android/libandroid.map.txt
index c82a1f6..bbd2783 100644
--- a/native/android/libandroid.map.txt
+++ b/native/android/libandroid.map.txt
@@ -198,6 +198,7 @@
     ASharedMemory_create; # introduced=26
     ASharedMemory_getSize; # introduced=26
     ASharedMemory_setProt; # introduced=26
+    ASharedMemory_dupFromJava; # introduced=27
     AStorageManager_delete;
     AStorageManager_getMountedObbPath;
     AStorageManager_isObbMounted;