Add month popup for new calendar picker
https://bugs.webkit.org/show_bug.cgi?id=110830

Reviewed by Kent Tamura.

Adding month popup view for use in the new calendar picker (Bug 109439).
YearListCell will grow in height when selected to reveal the buttons for
selecting the month.

No new tests. Code is not used yet.

* Resources/pagepopups/calendarPicker.js:
(YearListCell): A row inside the month popup. Contains buttons for choosing a month.
(YearListCell.prototype._recycleBin):
(YearListCell.prototype.reset): Resets a thrown away cell for reuse at the given row.
(YearListCell.prototype.height):
(YearListCell.prototype.setHeight):
(YearListView): List view showing YearListCells.
(YearListView.prototype.onMouseOver): If the mouse is over a month button, highlights it.
(YearListView.prototype.onMouseOut): De-highlights the month button.
(YearListView.prototype.setWidth): Set scroll view width to leave space for the scroll bar.
(YearListView.prototype.setHeight): Sets the scroll bar height as well.
(YearListView.prototype._animateRow): Animates the row height to open/close the YearListCell.
(YearListView.prototype.onCellHeightAnimatorDidStop): Keep this._runningAnimators and this._animatingRows up to date.
(YearListView.prototype.onCellHeightAnimatorStep): Update the cell height and position.
(YearListView.prototype.onClick): If this is a click on a month button, select the month.
(YearListView.prototype.rowAtScrollOffset): Calculates the row currently at the given offset.
(YearListView.prototype.scrollOffsetForRow): Calculates the current scroll offset of the given row.
(YearListView.prototype.prepareNewCell): Prepares a new or recycled YearListCell.
(YearListView.prototype.updateCells): Updates the position of the visible cells.
(YearListView.prototype.deselect): Deselects a row.
(YearListView.prototype.deselectWithoutAnimating): Deselects a row without the closing animation.
(YearListView.prototype.select): Selects a row.
(YearListView.prototype.selectWithoutAnimating): Deselects a row without the opening animation.
(YearListView.prototype.buttonForMonth): Returns the month button for a given month. Returns null if the cell is not visible.
(YearListView.prototype.dehighlightMonth): Dehighlights the month button.
(YearListView.prototype.highlightMonth): Highlights the month button.
(YearListView.prototype.show): Call when showing the year list view. Shows the given month as highlighted.
(YearListView.prototype.hide): Dispatches a did hide event which will be picked up by the CalendarPicker and the MonthPopupView will close.
(YearListView.prototype._moveHighlightTo): Used to move the month highlight in response to a key event.
(YearListView.prototype.onKeyDown): Arrow keys and PageUp/PageDown keys work.
(MonthPopupView): The popup view to be overlayed over the calendar picker.
(MonthPopupView.prototype.show): Takes the initialMonth to show and the calendarTableRect so we can overlay the year list view right on top of it.
(MonthPopupView.prototype.hide):
(MonthPopupView.prototype.onClick): Hides itself if the use clicks outside the year list view.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@144254 268f45cc-cd09-0410-ab3c-d52691b4dbfc