introduce tab IDs

    Tabs are identified by IDs now, instead of their position
    Refactored the save/restore code

Change-Id: I7133d55831201d097dc19ec938a85e7085f36749
diff --git a/src/com/android/browser/UiController.java b/src/com/android/browser/UiController.java
index a2de1d7..4fc37af 100644
--- a/src/com/android/browser/UiController.java
+++ b/src/com/android/browser/UiController.java
@@ -49,7 +49,7 @@
 
     void setActiveTab(Tab tab);
 
-    boolean switchToTab(int tabIndex);
+    boolean switchToTab(Tab tab);
 
     void closeCurrentTab();