Adding keyboard focus support for phones.

Change-Id: I2daab961d0727bc5d892db6b50ad0f51fe23873c
diff --git a/res/layout/apps_customize_widget.xml b/res/layout/apps_customize_widget.xml
index 0a196d0..6ba65c8 100644
--- a/res/layout/apps_customize_widget.xml
+++ b/res/layout/apps_customize_widget.xml
@@ -25,6 +25,7 @@
     launcher:blurColor="#FF6B8CF0"
     launcher:outlineColor="#FF8CD2FF"
 
+    android:background="@drawable/focusable_view_bg"
     android:focusable="true">
 
     <!-- The icon of the widget. -->