Improve a11y in minimal mode

Previously, the fullscreen button and timebar has been overlapped in minimal mode

PiperOrigin-RevId: 327606728

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

@@ -134,6 +134,7 @@
       android:layout_height="wrap_content"
       android:orientation="vertical"
       android:layout_gravity="bottom|end"
+      android:layout_marginBottom="@dimen/exo_custom_progress_thumb_size"
       android:visibility="invisible">
   </LinearLayout>