Remove magic paddings from bookmark view

 Use calculated sizes to correctly center without the need for
 "magic" padding values.

Change-Id: Ida64a80243df9bf05355dd1db1047fc16c10b726
diff --git a/res/layout/bookmarks.xml b/res/layout/bookmarks.xml
index bcabc03..4a13c6f 100644
--- a/res/layout/bookmarks.xml
+++ b/res/layout/bookmarks.xml
@@ -20,9 +20,7 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
-    android:paddingTop="@dimen/combo_paddingTop"
-    android:paddingLeft="@dimen/combo_paddingLeftRight"
-    android:paddingRight="@dimen/combo_paddingLeftRight">
+    android:paddingTop="@dimen/combo_paddingTop">
 
     <FrameLayout
         android:id="@+id/header_container"