Make preference category card dividers more dark theme compatible

// FREEBIE

res/drawable/preference_divider.xml

@@ -4,14 +4,14 @@
     <item>
         <shape>
             <padding android:top="1dp" android:right="0dp" android:bottom="0dp" android:left="0dp" />
-            <solid android:color="#d4d4d4" />
+            <solid android:color="?preference_divider_background_dark" />
         </shape>
     </item>
 
     <item>
         <shape>
             <padding android:top="1dp" android:right="0dp" android:bottom="0dp" android:left="0dp" />
-            <solid android:color="#dddddd" />
+            <solid android:color="?preference_divider_background_light" />
             <size android:height="20dp"/>
         </shape>
     </item>

res/values/attrs.xml

@@ -125,6 +125,9 @@
     <attr name="pref_ic_devices" format="reference" />
     <attr name="pref_ic_advanced" format="reference" />
 
+    <attr name="preference_divider_background_light" format="color" />
+    <attr name="preference_divider_background_dark" format="color"/>
+
     <attr name="app_protect_timeout_picker_color" format="reference"/>
 
     <declare-styleable name="CustomDefaultPreference">

res/values/themes.xml

@@ -216,6 +216,9 @@
         <item name="pref_ic_devices">@drawable/ic_laptop_black_24dp</item>
         <item name="pref_ic_advanced">@drawable/ic_advanced_black_24dp</item>
 
+        <item name="preference_divider_background_light">#dddddd</item>
+        <item name="preference_divider_background_dark">#d4d4d4</item>
+
         <item name="app_protect_timeout_picker_color">@style/BetterPickersDialogFragment.Light</item>
 
         <item name="group_members_dialog_icon">@drawable/ic_group_grey600_24dp</item>
@@ -346,6 +349,9 @@
         <item name="pref_ic_devices">@drawable/ic_laptop_white_24dp</item>
         <item name="pref_ic_advanced">@drawable/ic_advanced_white_24dp</item>
 
+        <item name="preference_divider_background_light">#222222</item>
+        <item name="preference_divider_background_dark">#101010</item>
+
         <item name="app_protect_timeout_picker_color">@style/BetterPickersDialogFragment</item>
 
         <item name="group_members_dialog_icon">@drawable/ic_group_white_24dp</item>