Set background for expanded search bar to white.

Bug: 24910704
Change-Id: I45630d62f9f89f5052bad943561ff4ab9e99e44c
diff --git a/res-common/layout/search_bar_expanded.xml b/res-common/layout/search_bar_expanded.xml
index c530299..241eb8e 100644
--- a/res-common/layout/search_bar_expanded.xml
+++ b/res-common/layout/search_bar_expanded.xml
@@ -20,7 +20,8 @@
     android:layout_height="match_parent"
     android:orientation="horizontal"
     android:gravity="center_vertical"
-    android:visibility="gone" >
+    android:visibility="gone"
+    android:background="@android:color/white">
 
     <ImageButton
         android:id="@+id/search_back_button"