https://bugs.webkit.org/show_bug.cgi?id=101821

Reviewed by Ojan Vafai.

Source/WebCore:

Make removeChild 9-14% faster by not walking the descendants looking for
frames when there's known to be no frames.

This is a more generalized version of the fix in Bug 101619 that only
avoided this walk when the whole document had no frames. This patch extends
it to skip traversing subtrees that have no frames by tracking the number of
frames in subtrees and then only walking those subtrees that are known to
contain frames in removeChild.

Test: fast/frames/parser-append-subframe-count.html

* dom/ContainerNode.cpp:
(WebCore::willRemoveChildren):
(WebCore::parserAppendChild):
(WebCore::parserRemoveChild):
(WebCore::parserInsertBefore):
    The parser may move nodes without doing frame disconnection so we
    must maintain the connected subframe count manually during these
    mutations.
* dom/ContainerNodeAlgorithms.cpp:
(WebCore::ChildFrameDisconnector::collectFrameOwners):
* dom/ContainerNodeAlgorithms.h:
(WebCore::ChildFrameDisconnector::ChildFrameDisconnector):
(ChildFrameDisconnector):
(WebCore::ChildFrameDisconnector::collectFrameOwners):
  Renamed from collectDescendant() to better reflect what it really does.
(WebCore::ChildFrameDisconnector::disconnectCollectedFrameOwners):
  Renamed from disconnect() to better reflect what it really does.
(WebCore::ChildFrameDisconnector::disconnect):
  New method that does the collection of frame owners on either the root
  or only it's descendants.
* dom/Node.cpp:
(WebCore::Node::connectedSubframeCount):
(WebCore::Node::incrementConnectedSubframeCount):
(WebCore::Node::decrementConnectedSubframeCount):
* dom/Node.h:
* dom/NodeRareData.h:
(WebCore::NodeRareData::NodeRareData):
(WebCore::NodeRareData::connectedSubframeCount):
(WebCore::NodeRareData::incrementConnectedSubframeCount):
(WebCore::NodeRareData::decrementConnectedSubframeCount):
* html/HTMLFrameOwnerElement.cpp:
(WebCore::HTMLFrameOwnerElement::setContentFrame):
(WebCore::HTMLFrameOwnerElement::disconnectContentFrame):

LayoutTests:

Add a test that when frames are moved around by the parser and not actually
detached we keep the subframe counters of ancestors consistent.

* fast/frames/parser-append-subframe-count-expected.txt: Added.
* fast/frames/parser-append-subframe-count.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140090 268f45cc-cd09-0410-ab3c-d52691b4dbfc