Fix order of playback controls in RTL layout

Issue: androidx/media#227

#minor-release

PiperOrigin-RevId: 497159283
(cherry picked from commit 8313af16)

library/ui/src/main/res/layout/exo_styled_player_control_view.xml

@@ -131,7 +131,8 @@
       android:background="@android:color/transparent"
       android:gravity="center"
       android:padding="@dimen/exo_styled_controls_padding"
-      android:clipToPadding="false">
+      android:clipToPadding="false"
+      android:layoutDirection="ltr">
 
     <ImageButton android:id="@id/exo_prev"
         style="@style/ExoStyledControls.Button.Center.Previous"/>