Add missing attrs to SimpleExoplayerView

They worked without being present in the declare-styleable,
but they need to be present for Android Studio auto-complete
to suggest them.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179047478

library/ui/src/main/res/values/attrs.xml

@@ -51,10 +51,13 @@
     <attr name="auto_show" format="boolean"/>
     <attr name="resize_mode"/>
     <attr name="surface_type"/>
+    <attr name="player_layout_id"/>
+    <!-- PlaybackControlView attrs -->
     <attr name="show_timeout"/>
     <attr name="rewind_increment"/>
     <attr name="fastforward_increment"/>
-    <attr name="player_layout_id"/>
+    <attr name="repeat_toggle_modes"/>
+    <attr name="show_shuffle_button"/>
     <attr name="controller_layout_id"/>
   </declare-styleable>