Updated assets for QSB launch and added a custom transition animation.

Using a fade animation for launching QSB because the standard intra-wallpaper transition
has changed.

Bug: 3223441
diff --git a/res/layout-xlarge-land/launcher.xml b/res/layout-xlarge-land/launcher.xml
index 7516796..f93506e 100644
--- a/res/layout-xlarge-land/launcher.xml
+++ b/res/layout-xlarge-land/launcher.xml
@@ -63,7 +63,7 @@
                 android:layout_width="wrap_content"
                 android:layout_height="match_parent"
                 android:layout_marginLeft="16dp"
-                android:background="@drawable/textfield_start"
+                android:background="@drawable/textfield_home_start"
                 android:orientation="horizontal">
                 <!-- Global search icon -->
                 <ImageView
@@ -84,7 +84,7 @@
             <LinearLayout
                 android:layout_width="wrap_content"
                 android:layout_height="match_parent"
-                android:background="@drawable/textfield_end"
+                android:background="@drawable/textfield_home_end"
                 android:orientation="horizontal">
                 <!-- Voice search icon -->
                 <ImageView