Fix "Left" & "Right" in the wrong sides for LTR language

Root cause: In the LTR language, the "Left" & "Right" options should be in the opposite sides -- currently "Left" is in the right side and "Right" is in the left side (Same as the English version) and should be changed.
Solution: Keep ltr layout direction.

Bug: 190354990
Test: Manual test
Change-Id: I47b71b3db7c834984202513e2cac6c4d787518dc

res/layout/preference_balance_slider.xml

@@ -72,6 +72,7 @@
         <LinearLayout
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:layoutDirection="ltr"
             android:orientation="vertical">
 
             <com.android.settings.accessibility.BalanceSeekBar