Implement month picking to calendar picker

Implement month picking to calendar picker
https://bugs.webkit.org/show_bug.cgi?id=101333

Reviewed by Kent Tamura.

.:

* ManualTests/forms/calendar-picker.html: Added test for month picker.

Source/WebCore:

This adds month picker mode to CalendarPicker.

No new tests. Tests will be added later when this feature is enabled in DRT.

* Resources/pagepopups/calendarPicker.css:
(.month-mode .day): Remove rounded corners when in month mode.
* Resources/pagepopups/calendarPicker.js:
(Month.createFromToday): Creates month containing today.
(CalendarPicker): Set this.selectionConstructor to Day or Month depending on the mode. Create DayTables or MonthPickerDaysTable depending on the mode.
(CalendarPicker.prototype.handleToday):
(CalendarPicker.prototype._layoutButtons):
(DaysTable.prototype._renderMonth): Set element.dataset.monthValue for all date nodes.
(DaysTable.prototype._markRangeAsSelected): Marks all day nodes in range as selected.
(DaysTable.prototype.selectRange): Selects a day.
(DaysTable.prototype.selectRangeAndShowEntireRange): Same as selectRange.
(DaysTable.prototype._selectRangeContainingNode):
(DaysTable.prototype._rangeForNode): Returns Day for node.
(DaysTable.prototype.startDate): Start datetime of visible date range. This value is inclusive.
(DaysTable.prototype.endDate): End datetime of visible date range. This value is exclusive.
(DaysTable.prototype._handleKey):
(MonthPickerDaysTable):
(MonthPickerDaysTable.prototype._markRangeAsSelected): Marks all day nodes in range as selected.
(MonthPickerDaysTable.prototype.selectRange): Selects month. If month is not visible, navigates to that month.
(MonthPickerDaysTable.prototype.selectRangeAndShowEntireRange): Selects month. Navigates to the month.
(MonthPickerDaysTable.prototype._rangeForNode): Returns Month for node.
(MonthPickerDaysTable.prototype._handleKey): Arrow keys simply move the selection forwards or backwards.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@133722 268f45cc-cd09-0410-ab3c-d52691b4dbfc