fix lint: legacy fab styling

src/main/res/drawable/fab_label_background.xml

@@ -1,11 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<shape xmlns:android="http://schemas.android.com/apk/res/android">
-    <solid android:color="@color/black_semi_transparent"/>
-    <padding
-        android:left="@dimen/standard_padding"
-        android:top="4dp"
-        android:right="@dimen/standard_padding"
-        android:bottom="4dp"/>
-    <corners
-        android:radius="2dp"/>
-</shape>

src/main/res/values/colors.xml

@@ -24,8 +24,6 @@
     <color name="list_item_lastmod_and_filesize_text">@color/secondaryTextColor</color>
     <color name="black">#000000</color>
     <color name="white">#FFFFFF</color>
-    <color name="fab_white">#fafafa</color>
-    <color name="black_semi_transparent">#B2000000</color>
     <color name="textColor">@color/black</color>
     <color name="disabled_text">#ff888888</color>
     <color name="list_divider_background">#eee</color>

src/main/res/values/styles.xml

@@ -191,11 +191,6 @@
 		<item name="colorAccent">@color/color_accent</item>
 	</style>
 
-	<style name="menu_labels_style">
-		<item name="android:background">@drawable/fab_label_background</item>
-		<item name="android:textColor">@color/fab_white</item>
-	</style>
-
 	<style name="NavigationView_ItemTextAppearance">
 		<item name="android:ellipsize">end</item>
 		<item name="android:listDivider">@color/transparent</item>