Remove background for button bar for watch devices.

Bug: 31222864
Change-Id: Idbe73478f3cff45ed502853ffa1e426d475dbf3e
diff --git a/core/res/res/values-watch/styles_material.xml b/core/res/res/values-watch/styles_material.xml
index d09119f..a5e4845 100644
--- a/core/res/res/values-watch/styles_material.xml
+++ b/core/res/res/values-watch/styles_material.xml
@@ -68,8 +68,6 @@
         <item name="breakStrategy">balanced</item>
     </style>
 
-    <style name="Widget.Material.ButtonBar" parent="Widget.Material.BaseButtonBar" />
-
     <style name="TextAppearance.Material.NumberPicker" parent="TextAppearance.Material.Body1">
         <item name="textSize">@dimen/text_size_medium_material</item>
     </style>
diff --git a/core/res/res/values/styles_material.xml b/core/res/res/values/styles_material.xml
index 224e3b7..22bdf7e 100644
--- a/core/res/res/values/styles_material.xml
+++ b/core/res/res/values/styles_material.xml
@@ -553,11 +553,7 @@
         <item name="textOff">@string/capital_off</item>
     </style>
 
-    <style name="Widget.Material.BaseButtonBar">
-        <item name="background">?attr/colorBackgroundFloating</item>
-    </style>
-
-    <style name="Widget.Material.ButtonBar" parent="Widget.Material.BaseButtonBar">
+    <style name="Widget.Material.ButtonBar">
         <item name="background">@null</item>
     </style>