Update style to match Oreo Settings

Use the same theme settings the Oreo Settings app uses,
so our preferences don't look out of place.

Change-Id: Idafccb09a3b23de7f568e0ab32b602fe11bd0af3
diff --git a/res/values/styles.xml b/res/values/styles.xml
index 480a8ea..daaa69f 100644
--- a/res/values/styles.xml
+++ b/res/values/styles.xml
@@ -75,14 +75,38 @@
         <item name="android:textStyle">normal</item>
     </style>
 
-    <style name="Preference">
-        <item name="android:layout">@layout/preference_material_settings</item>
+    <style name="DialogPreferenceStyle" parent="@*android:style/Preference.DeviceDefault.DialogPreference">
+        <item name="allowDividerAbove">false</item>
+        <item name="allowDividerBelow">true</item>
+        <item name="singleLineTitle">false</item>
+        <item name="android:iconSpaceReserved">true</item>
     </style>
 
     <style name="EditTextPreference" parent="@*android:style/Preference.Material.DialogPreference.EditTextPreference">
         <item name="android:dialogLayout">@layout/preference_dialog_edittext</item>
     </style>
 
+    <style name="PreferenceCategoryStyle" parent="@*android:style/Preference.DeviceDefault.Category">
+        <item name="allowDividerAbove">true</item>
+        <item name="allowDividerBelow">true</item>
+        <item name="android:layout">@layout/preference_category_material_settings</item>
+    </style>
+
+    <style name="PreferenceFragmentStyle" parent="@*android:style/PreferenceFragment.Material">
+        <item name="allowDividerAfterLastItem">false</item>
+        <item name="android:layout">@layout/preference_list_fragment</item>
+    </style>
+
+    <style name="PreferenceStyle" parent="@*android:style/Preference.DeviceDefault">
+        <item name="allowDividerAbove">false</item>
+        <item name="allowDividerBelow">true</item>
+        <item name="singleLineTitle">false</item>
+        <item name="android:layout">@layout/preference_material_settings</item>
+    </style>
+
+    <style name="PreferenceTheme">
+    </style>
+
     <style name="PreferenceHeaderPanelSinglePane">
         <item name="android:layout_marginStart">0dp</item>
         <item name="android:layout_marginEnd">0dp</item>
@@ -124,8 +148,8 @@
     <style name="SettingsPreferenceHeaderList" parent="@*android:style/PreferenceHeaderList">
     </style>
 
-    <style name="PreferenceFragmentStyle" parent="@*android:style/PreferenceFragment.Material">
-        <item name="android:layout">@layout/preference_list_fragment</item>
+    <style name="SwitchPreferenceStyle" parent="@style/PreferenceStyle">
+        <item name="widgetLayout">@*android:layout/preference_widget_switch</item>
     </style>
 
     <style name="VertDivider">