// `bookmarksDatabaseHelper` is used in `onCreate()`, `onOptionsItemSelected()`, `onBackPressed()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveBookmark()`, `onSaveBookmarkFolder()`,
// `onMoveToFolder()`, `deleteBookmarkFolderContents()`, `loadFolder()`, and `onDestroy()`.
// `bookmarksDatabaseHelper` is used in `onCreate()`, `onOptionsItemSelected()`, `onBackPressed()`, `onCreateBookmark()`, `onCreateBookmarkFolder()`, `onSaveBookmark()`, `onSaveBookmarkFolder()`,
// `onMoveToFolder()`, `deleteBookmarkFolderContents()`, `loadFolder()`, and `onDestroy()`.