Replace shouldLazyAttach bool with an enum for readability

Replace shouldLazyAttach bool with an enum for readability
https://bugs.webkit.org/show_bug.cgi?id=111503

Reviewed by Dimitri Glazkov.

No behavioral change.

* bindings/cpp/WebDOMNodeCustom.cpp:
(WebDOMNode::insertBefore):
(WebDOMNode::replaceChild):
(WebDOMNode::appendChild):
* bindings/js/JSNodeCustom.cpp:
(WebCore::JSNode::insertBefore):
(WebCore::JSNode::replaceChild):
(WebCore::JSNode::appendChild):
* bindings/v8/custom/V8NodeCustom.cpp:
(WebCore):
(WebCore::V8Node::insertBeforeMethodCustom):
(WebCore::V8Node::replaceChildMethodCustom):
(WebCore::V8Node::appendChildMethodCustom):
* dom/ContainerNode.cpp:
(WebCore):
(WebCore::ContainerNode::insertBefore):
(WebCore::ContainerNode::replaceChild):
(WebCore::ContainerNode::appendChild):
(WebCore::updateTreeAfterInsertion):
* dom/ContainerNode.h:
(ContainerNode):
* dom/Node.cpp:
(WebCore::Node::insertBefore):
(WebCore::Node::replaceChild):
(WebCore::Node::appendChild):
* dom/Node.h:
(Node):
* editing/AppendNodeCommand.cpp:
(WebCore::AppendNodeCommand::doApply):
* editing/InsertNodeBeforeCommand.cpp:
(WebCore::InsertNodeBeforeCommand::doApply):
* html/shadow/MediaControlsApple.cpp:
(WebCore::MediaControlsApple::createControls):
* html/shadow/MediaControlsBlackBerry.cpp:
(WebCore::MediaControlsBlackBerry::createControls):
* html/shadow/MediaControlsChromium.cpp:
(WebCore::MediaControlsChromium::initializeControls):
* html/shadow/MediaControlsChromiumAndroid.cpp:
(WebCore::MediaControlsChromiumAndroid::createControls):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@144891 268f45cc-cd09-0410-ab3c-d52691b4dbfc