testFontSizeDoesntOverrideStyleAttrMultiNode() {
    setUpFontSizeTests();
    FIELDMOCK.$replay();

    HELPER.select('23', 1, '56', 2);  // Selects 3456.
    FORMATTER.execCommandInternal(BasicTextFormatter.COMMAND.FONT_SIZE, 6);

    assertFontSizes(
        'New font size shouldn\'t override existing font size before ' +
            'selection, but still override existing font size in last span',
        {'2': 2, '23': null, '3': 32, '4': 32, '56': 32});

    FIELDMOCK.$verify();
  }
Makes sure the font size style is not removed when only a part of the
element with font size style is selected during the font size command, but
is removed for another element that is fully selected.
@suppress {visibility} suppression added to enable type checking