[LayoutReloaded] Remove border/padding/contentBox() functions from Layout.Box

[LayoutReloaded] Remove border/padding/contentBox() functions from Layout.Box
https://bugs.webkit.org/show_bug.cgi?id=183761

Reviewed by Antti Koivisto.

Display.Box has them.

* LayoutReloaded/FormattingContext/BlockFormatting/BlockFormattingContext.js:
(BlockFormattingContext.prototype._computeOutOfFlowWidth):
(BlockFormattingContext.prototype._computeOutOfFlowHeight):
(BlockFormattingContext.prototype._horizontalConstraint):
(BlockFormattingContext.prototype._contentHeight):
(BlockFormattingContext.prototype._adjustBottomWithFIXME):
(BlockFormattingContext.prototype._computeOutOfFlowPosition):
* LayoutReloaded/FormattingContext/FloatingContext.js:
(FloatingContext.prototype._availableSpace):
* LayoutReloaded/FormattingContext/FormattingContext.js:
(FormattingContext.prototype.absoluteBorderBox):
(FormattingContext.prototype.absolutePaddingBox):
(FormattingContext.prototype.absoluteContentBox):
* LayoutReloaded/LayoutTree/Box.js:
(Layout.Box.prototype.isDescendantOf):
(Layout.Box):
(Layout.Box.prototype.borderBox): Deleted.
(Layout.Box.prototype.paddingBox): Deleted.
(Layout.Box.prototype.contentBox): Deleted.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@229734 268f45cc-cd09-0410-ab3c-d52691b4dbfc