Added support for docked stack

Docked stacks occupy a dedicated region on a display.
When a docked stack is present all other static stacks bounds
are restricted to the region of the screen not occupied by
the docked stack.

Change-Id: I6aec3aa19c41a7e756375002f3a925977b5533b5
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 2b26b42..99e9fe6 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -173,7 +173,7 @@
     void updateDisplayInfo() {
         mDisplay.getDisplayInfo(mDisplayInfo);
         for (int i = mStacks.size() - 1; i >= 0; --i) {
-            mStacks.get(i).updateDisplayInfo();
+            mStacks.get(i).updateDisplayInfo(null);
         }
     }