docs: public Bundle saveInstanceState(Bundle savedInstanceState) {
          if (savedInstanceState != null) {
              if (!mDrawerBuilder.mAppended) {
                  savedInstanceState = mDrawerBuilder.mAdapter.saveInstanceState(savedInstanceState, BUNDLE_SELECTION);
                  savedInstanceState.putInt(BUNDLE_STICKY_FOOTER_SELECTION, mDrawerBuilder.mCurrentStickyFooterSelection);
                  savedInstanceState.putBoolean(BUNDLE_DRAWER_CONTENT_SWITCHED, switchedDrawerContent());
              } else {
                  savedInstanceState = mDrawerBuilder.mAdapter.saveInstanceState(savedInstanceState, BUNDLE_SELECTION_APPENDED);
                  savedInstanceState.putInt(BUNDLE_STICKY_FOOTER_SELECTION_APPENDED, mDrawerBuilder.mCurrentStickyFooterSelection);
                  savedInstanceState.putBoolean(BUNDLE_DRAWER_CONTENT_SWITCHED_APPENDED, switchedDrawerContent());
              }
          }
          return savedInstanceState;
      }