Rename Node::childNode(index) to traverseToChildAt(index) for clarity
https://bugs.webkit.org/show_bug.cgi?id=136825

Reviewed by Benjamin Poulain.

Rename Node::childNode(index) to traverseToChildAt(index) to make it
clearer that the method is actually traversing the children and thus
potentially expensive.

This patch also avoids calling traverseToChildAt() in a couple of
easily avoidable cases.

No new tests, no behavior change.

* WebCore.exp.in:
* WebCore.order:
Remove symbol for ContainerNode::childNode() as it was renamed. It does
not seem we need to expose ContainerNode::traverseToChildAt().

* accessibility/AccessibilityObject.cpp:
(WebCore::AccessibilityObject::stringForVisiblePositionRange):
(WebCore::AccessibilityObject::lengthForVisiblePositionRange):
* accessibility/ios/WebAccessibilityObjectWrapperIOS.mm:
(-[WebAccessibilityObjectWrapper arrayOfTextForTextMarkers:attributed:]):
* accessibility/mac/WebAccessibilityObjectWrapperMac.mm:
(-[WebAccessibilityObjectWrapper doAXAttributedStringForTextMarkerRange:]):
Mechanical renaming.

* dom/ContainerNode.cpp:
(WebCore::ContainerNode::traverseToChildAt):
(WebCore::ContainerNode::childNode): Deleted.
* dom/ContainerNode.h:
(WebCore::Node::traverseToChildAt):
(WebCore::Node::childNode): Deleted.
* dom/Node.h:
- Rename Node / ContainerNode's childNode(index) to
  traverseToChildAt(index) to make it clear that it is actually
  traversing the children and thus potentially expensive.
- Clean up the implementation of ContainerNode::traverseToChildAt()
  to avoid the use of an extra |i| variable.

* dom/Position.cpp:
(WebCore::Position::computeNodeBeforePosition):
Avoid calling traverseToChildAt(-1). Relying on the unsigned argument
wrapping and the method returning null in this case is a bit obscure
and causes unnecessary traversal of all children.

(WebCore::Position::computeNodeAfterPosition):
(WebCore::Position::previous):
(WebCore::Position::next):
Mechanical renaming and update variable names to stop using
abbreviations as per coding style.

* dom/PositionIterator.h:
(WebCore::PositionIterator::PositionIterator):
* dom/Range.cpp:
(WebCore::Range::insertNode):
(WebCore::Range::checkNodeWOffset):
(WebCore::Range::firstNode):
(WebCore::Range::pastLastNode):
* dom/RangeBoundaryPoint.h:
(WebCore::RangeBoundaryPoint::set):
* editing/BreakBlockquoteCommand.cpp:
(WebCore::BreakBlockquoteCommand::doApply):
* editing/CompositeEditCommand.cpp:
(WebCore::CompositeEditCommand::removeChildrenInRange):
* editing/DeleteSelectionCommand.cpp:
(WebCore::DeleteSelectionCommand::handleGeneralDelete):
* editing/InsertParagraphSeparatorCommand.cpp:
(WebCore::InsertParagraphSeparatorCommand::doApply):
* editing/TextIterator.cpp:
(WebCore::nextInPreOrderCrossingShadowBoundaries):
(WebCore::TextIterator::node):
(WebCore::SimplifiedBackwardsTextIterator::SimplifiedBackwardsTextIterator):
* editing/VisibleUnits.cpp:
(WebCore::nextLinePosition):
* editing/cocoa/HTMLConverter.mm:
(WebCore::editingAttributedStringFromRange):
Mechanical renaming.

* inspector/DOMPatchSupport.cpp:
(WebCore::DOMPatchSupport::innerPatchChildren):
Iterate over children while incrementing the |i| variable to avoid
calling traverseToChildAt(index) repeatedly and thus traversing the
children from the beginning every time.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@173684 268f45cc-cd09-0410-ab3c-d52691b4dbfc