Keep drawer open in xlarge-land and add float fps

platform_tools/android/apps/viewer/src/main/res/layout/activity_main.xml

 <?xml version="1.0" encoding="utf-8"?>
 
 <android.support.v4.widget.DrawerLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/drawerLayout"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
     <!-- The main content view -->
-    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-        xmlns:tools="http://schemas.android.com/tools"
-        android:id="@+id/mainLayout"
-        android:orientation="vertical"
+    <RelativeLayout
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        tools:context=".ViewerActivity">
+        android:layout_height="match_parent">
 
-        <SurfaceView
-            android:id="@+id/surfaceView"
+        <!-- We use mainLayout for recreating SurfaceView -->
+        <LinearLayout
+            android:id="@+id/mainLayout"
             android:layout_width="match_parent"
-            android:layout_height="match_parent"
-            android:layout_centerVertical="true"
-            android:layout_centerHorizontal="true" />
+            android:layout_height="match_parent">
+            <SurfaceView
+                android:id="@+id/surfaceView"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:layout_centerVertical="true"
+                android:layout_centerHorizontal="true" />
+        </LinearLayout>
 
-    </LinearLayout>
+        <TextView
+            android:layout_width="100dp"
+            android:layout_height="wrap_content"
+            android:layout_margin="10dp"
+            android:padding="10dp"
+            android:background="@android:color/holo_blue_dark"
+            android:textColor="@android:color/white"
+            android:text="  100.000ms"
+            android:id="@+id/fpsFloatText"
+            android:visibility="invisible"
+            android:layout_alignParentBottom="true"
+            android:layout_alignParentEnd="true" />
+
+    </RelativeLayout>
 
     <!-- The navigation drawer -->
     <ListView android:id="@+id/leftDrawer"
         android:layout_width="240dp"
         android:layout_height="match_parent"
         android:layout_gravity="start"
         android:choiceMode="singleChoice"
         android:divider="@android:color/transparent"
         android:dividerHeight="0dp"
         android:background="@android:color/background_light"/>
 </android.support.v4.widget.DrawerLayout>