Refactor to use BDD idea

[takahirom]

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File name	Image
TimetableItemDetailS creen - when server is operational - whe n launch - click boo kmark - click bookma rk again - it should show unbookmarked s ession_compare.png
TimetableScreen - wh en server is operati onal - it should sho w timetable items_co mpare.png
TimetableScreen - wh en server is operati onal - click first s ession bookmark - it should show bookmar ked session_compare. png
TimetableItemDetailS creen - when server is operational - whe n font scale is larg e - it should show s mall font session de tail_compare.png
TimetableItemDetailS creen - when server is operational - whe n launch - it should show session detail title_compare.png
TimetableItemDetailS creen - when server is operational - whe n launch - click boo kmark - it should sh ow bookmarked sessio n_compare.png
TimetableItemDetailS creen - when server is operational - whe n font scale is smal l - it should show s mall font session de tail_compare.png
TimetableItemDetailS creenTest.runTest[Ti metableItemDetailScr een - when server is operational - when launch - it should b e appropriately acce ssible]_compare.png
TimetableItemDetailS creen - when server is operational - whe n font scale is huge - it should show sm all font session det ail_compare.png
TimetableItemDetailS creen - when server is operational - whe n launch - scroll - it should show scrol led session detail_c ompare.png
TimetableScreen - wh en server is down - it should show error message_compare.png
TimetableScreen - wh en server is operati onal - click timetab le ui type change - it should change tim etable ui type_compa re.png
TimetableItemDetailT opAppBarUnSelectable Preview_compare.png
TimeTableItemDetailC ontentPreview_compar e.png
PreviewTimetableScre enDark_compare.png
FontPreview_compare. png
TimeTableItemDetailC ontentWithEnglishPre view_compare.png
TimetableItemDetailT opAppBarPreview_comp are.png
TimetableItemDetailB ottomAppBarPreview_c ompare.png
TimeTableItemDetailH eadlinePreview_compa re.png
TimeTableItemDetailC ontentWithMixedPrevi ew_compare.png
TimetableItemDetailB ottomAppBarBookmarke dPreview_compare.png
TimetableItemDetailS creenPreview_compare .png
TimeTableItemDetailS ummaryCardPreview_co mpare.png