[binder] Move Rust ping_binder() to external API

The ping_binder() API should be publicly usable on Rust Binder objects.
This change moves this method from the IBinderInternal trait to the
IBinder trait for more general use.

Test: atest rustBinderTest
Bug: 195455757
Change-Id: I1751d9d69ee96197a8f2b577d0150b42445a7d5f
diff --git a/libs/binder/rust/src/binder.rs b/libs/binder/rust/src/binder.rs
index 7895a72..467e51e 100644
--- a/libs/binder/rust/src/binder.rs
+++ b/libs/binder/rust/src/binder.rs
@@ -192,9 +192,6 @@
     /// Is this object still alive?
     fn is_binder_alive(&self) -> bool;
 
-    /// Send a ping transaction to this object
-    fn ping_binder(&mut self) -> Result<()>;
-
     /// Indicate that the service intends to receive caller security contexts.
     #[cfg(not(android_vndk))]
     fn set_requesting_sid(&mut self, enable: bool);
@@ -270,6 +267,9 @@
     /// The recipient will no longer be called if this object
     /// dies.
     fn unlink_to_death(&mut self, recipient: &mut DeathRecipient) -> Result<()>;
+
+    /// Send a ping transaction to this object
+    fn ping_binder(&mut self) -> Result<()>;
 }
 
 /// Opaque reference to the type of a Binder interface.