code: @Override
      public void removeTextChangedListener(TextWatcher watcher) {
          if (watcher == mInternalTextWatcher) {
              if (mIsWatchingText) {
                  super.removeTextChangedListener(mInternalTextWatcher);
                  mIsWatchingText = false;
              }
          } else {
              // Other watchers are added
              mExternalTextWatchers.remove(watcher);
          }
      }
docs: Removes a {@link TextWatcher} from this class. Note that this function servers as the
  counterpart to {@link #addTextChangedListener(TextWatcher)}).
  
  @param watcher the {@link TextWatcher} to remove