nullptr cleanup in RenderFooBox classes

nullptr cleanup in RenderFooBox classes
https://bugs.webkit.org/show_bug.cgi?id=143182

Patch by Joonghun Park <jh718.park@samsung.com> on 2015-03-29
Reviewed by Ryosuke Niwa.

No new tests, no behavior changes

Replace 0 with nullptr in RenderFooBox classes.

* rendering/RenderBox.cpp:
(WebCore::RenderBox::RenderBox):
(WebCore::RenderBox::paintFillLayer):
(WebCore::RenderBox::shrinkLogicalWidthToAvoidFloats):
(WebCore::RenderBox::containingBlockAvailableLineWidthInRegion):
(WebCore::RenderBox::renderBoxRegionInfo):
(WebCore::RenderBox::computePositionedLogicalWidthUsing):
(WebCore::RenderBox::computePositionedLogicalHeightUsing):
(WebCore::RenderBox::computePositionedLogicalWidthReplaced):
(WebCore::RenderBox::positionForPoint):
(WebCore::RenderBox::layoutOverflowRectForPropagation):
* rendering/RenderBox.h:
(WebCore::RenderBox::setMarginBefore):
(WebCore::RenderBox::setMarginAfter):
(WebCore::RenderBox::setMarginStart):
(WebCore::RenderBox::setMarginEnd):
(WebCore::RenderBox::createAnonymousBoxWithSameTypeAs):
(WebCore::RenderBox::setInlineBoxWrapper):
* rendering/RenderBoxModelObject.cpp:
(WebCore::RenderBoxModelObject::willBeDestroyed):
(WebCore::RenderBoxModelObject::paintMaskForTextFillBox):
(WebCore::RenderBoxModelObject::paintBorderSides):
(WebCore::RenderBoxModelObject::firstLetterRemainingText):
* rendering/RenderBoxModelObject.h:
(WebCore::RenderBoxModelObject::moveChildTo):
(WebCore::RenderBoxModelObject::moveAllChildrenTo):
(WebCore::RenderBoxModelObject::moveChildrenTo):
* rendering/RenderDeprecatedFlexibleBox.cpp:
(WebCore::FlexBoxIterator::reset):
(WebCore::FlexBoxIterator::next):
* rendering/RenderDeprecatedFlexibleBox.h:
* rendering/RenderFlexibleBox.cpp:
(WebCore::RenderFlexibleBox::firstLineBaseline):
(WebCore::RenderFlexibleBox::computeMainAxisExtentForChild):
* rendering/RenderLineBoxList.cpp:
(WebCore::RenderLineBoxList::deleteLineBoxTree):
(WebCore::RenderLineBoxList::extractLineBox):
(WebCore::RenderLineBoxList::deleteLineBoxes):
(WebCore::RenderLineBoxList::checkConsistency):
* rendering/RenderLineBoxList.h:
(WebCore::RenderLineBoxList::RenderLineBoxList):
* rendering/RenderListBox.cpp:
(WebCore::RenderListBox::enclosingScrollableArea):
(WebCore::RenderListBox::setHasVerticalScrollbar):
* rendering/RenderListBox.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@182127 268f45cc-cd09-0410-ab3c-d52691b4dbfc