Fix issue #1999179: search -> click result -> press home = search dialog is shown then hidden

Re-arrange various things to ensure that the search dialog is told about system windows being
closed before it is told about the navigation back to home.
diff --git a/core/java/android/app/IActivityManager.java b/core/java/android/app/IActivityManager.java
index b1b5282..f6ef549 100644
--- a/core/java/android/app/IActivityManager.java
+++ b/core/java/android/app/IActivityManager.java
@@ -268,7 +268,9 @@
             throws RemoteException;
 
     public void killApplicationWithUid(String pkg, int uid) throws RemoteException;
-        
+    
+    public void closeSystemDialogs(String reason) throws RemoteException;
+    
     /*
      * Private non-Binder interfaces
      */
@@ -424,4 +426,5 @@
     int UNREGISTER_ACTIVITY_WATCHER_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+93;
     int START_ACTIVITY_IN_PACKAGE_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+94;
     int KILL_APPLICATION_WITH_UID_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+95;
+    int CLOSE_SYSTEM_DIALOGS_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+96;
 }