Make home setting edge-to-edge

Bug:139437515
Test:Manual
Change-Id: Iadd7fadbd48f80a77880bfc3118be6c3ed7e3040
diff --git a/AndroidManifest-common.xml b/AndroidManifest-common.xml
index 8db875b..555cc73 100644
--- a/AndroidManifest-common.xml
+++ b/AndroidManifest-common.xml
@@ -169,7 +169,7 @@
         <activity
             android:name="com.android.launcher3.settings.SettingsActivity"
             android:label="@string/settings_button_text"
-            android:theme="@android:style/Theme.DeviceDefault.Settings"
+            android:theme="@style/HomeSettingsTheme"
             android:autoRemoveFromRecents="true">
             <intent-filter>
                 <action android:name="android.intent.action.APPLICATION_PREFERENCES" />
diff --git a/res/values/styles.xml b/res/values/styles.xml
index 339aef5..80c791c 100644
--- a/res/values/styles.xml
+++ b/res/values/styles.xml
@@ -130,6 +130,10 @@
         <item name="widgetsTheme">@style/WidgetContainerTheme</item>
     </style>
 
+    <style name="HomeSettingsTheme" parent="@android:style/Theme.DeviceDefault.Settings">
+        <item name="android:navigationBarColor">@android:color/transparent</item>
+    </style>
+
     <!--
     Theme overrides to element on homescreen, i.e., which are drawn on top on wallpaper.
     Various foreground colors are overridden to be workspaceTextColor so that they are properly