Fix memory leak in bookmarks page

 Bug: 3378680

Change-Id: I845b7b69793080ecb1dd2551d16a36ca3949a564
diff --git a/src/com/android/browser/BrowserBookmarksPage.java b/src/com/android/browser/BrowserBookmarksPage.java
index f20583a..7475237 100644
--- a/src/com/android/browser/BrowserBookmarksPage.java
+++ b/src/com/android/browser/BrowserBookmarksPage.java
@@ -394,6 +394,8 @@
         mCrumbs.setController(null);
         mCrumbs = null;
         getLoaderManager().destroyLoader(LOADER_BOOKMARKS);
+        mAdapter = null;
+        CombinedBookmarkHistoryView.getIconListenerSet().removeListener(this);
     }
 
     @Override