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/PieControl.java b/src/com/android/browser/PieControl.java
index 684cd1a..8bcd972 100644
--- a/src/com/android/browser/PieControl.java
+++ b/src/com/android/browser/PieControl.java
@@ -142,7 +142,7 @@
         mUi.captureTab(mUi.getActiveTab());
         mTabAdapter.setTabs(tabs);
         PieStackView sym = (PieStackView) mShowTabs.getPieView();
-        sym.setCurrent(mUiController.getTabControl().getCurrentIndex());
+        sym.setCurrent(mUiController.getTabControl().getCurrentPosition());
 
     }
 
@@ -281,8 +281,7 @@
             view.setOnClickListener(new OnClickListener() {
                 @Override
                 public void onClick(View v) {
-                    mUiController.switchToTab(mUiController.getTabControl()
-                            .getTabIndex(tab));
+                    mUiController.switchToTab(tab);
                 }
             });
             return view;