Showing docked stack divider window.

When there is docked stack, we want to show a "handle" through which the
user will resize the docked stack. We add it from the system process,
because we want to avoid IPC calls.

Change-Id: If15fd2a0fcb7077446d1ba6c533acb3028a42039
diff --git a/core/java/android/view/WindowManager.java b/core/java/android/view/WindowManager.java
index 45bc1df..92e473d 100644
--- a/core/java/android/view/WindowManager.java
+++ b/core/java/android/view/WindowManager.java
@@ -226,6 +226,7 @@
             @ViewDebug.IntToString(from = TYPE_PRIVATE_PRESENTATION, to = "TYPE_PRIVATE_PRESENTATION"),
             @ViewDebug.IntToString(from = TYPE_VOICE_INTERACTION, to = "TYPE_VOICE_INTERACTION"),
             @ViewDebug.IntToString(from = TYPE_VOICE_INTERACTION_STARTING, to = "TYPE_VOICE_INTERACTION_STARTING"),
+            @ViewDebug.IntToString(from = TYPE_DOCK_DIVIDER, to = "TYPE_DOCK_DIVIDER"),
         })
         public int type;
 
@@ -565,6 +566,13 @@
         public static final int TYPE_VOICE_INTERACTION_STARTING = FIRST_SYSTEM_WINDOW+33;
 
         /**
+         * Window for displaying a handle used for resizing docked stacks. This window is owned
+         * by the system process.
+         * @hide
+         */
+        public static final int TYPE_DOCK_DIVIDER = FIRST_SYSTEM_WINDOW+34;
+
+        /**
          * End of types of system windows.
          */
         public static final int LAST_SYSTEM_WINDOW      = 2999;