Implement ComboView for Bookmarks, History and SavedPages

 - Replaces ComboViewActivity for PhoneUi.
 - Lives as part of the BrowserActivity's ViewTree.
 - Avoids construction of ComboViewActivity everytime the bookmarks screen is opened.

Change-Id: Ic7042de731a4cc2107a297c9f7d4356bc2c30f2e
diff --git a/src/com/android/browser/BrowserBookmarksPage.java b/src/com/android/browser/BrowserBookmarksPage.java
index 3fea1ed..d026b09 100644
--- a/src/com/android/browser/BrowserBookmarksPage.java
+++ b/src/com/android/browser/BrowserBookmarksPage.java
@@ -353,6 +353,13 @@
             mCallbacks = new CombinedBookmarksCallbackWrapper(
                     (CombinedBookmarksCallbacks) getActivity());
         }
+        if (mCallbacks == null) {
+            View cb = getActivity().getWindow().getDecorView().findViewById(R.id.combo_view_container);
+            if (cb != null && cb instanceof CombinedBookmarksCallbacks) {
+                mCallbacks = new CombinedBookmarksCallbackWrapper(
+                        (CombinedBookmarksCallbacks) cb);
+            }
+        }
     }
 
     @Override