DocumentOrderedMap doesn't need to have two HashMaps

DocumentOrderedMap doesn't need to have two HashMaps
https://bugs.webkit.org/show_bug.cgi?id=116167

Reviewed by Geoffrey Garen.

Previously, we had two hash maps: m_map and m_duplicateCounts in DocumentOrderedMap to keep track
of the first element and the number of duplicates for a given name. This patch simplifies this structure
by having a single hash map that contains both the pointer and the number of duplicates.

In addition, this patch fixes a regression introduced in r149652 that window and document name maps
were not updated for some elements inside a SVG use element, and makes use of the newly added list of
the matching elements in SelectorQuery.

* dom/DocumentOrderedMap.cpp:
(WebCore::DocumentOrderedMap::clear): Updated to use the new hash map.
(WebCore::DocumentOrderedMap::add): Ditto.
(WebCore::DocumentOrderedMap::remove): Ditto.
(WebCore::DocumentOrderedMap::get): Ditto.
(WebCore::DocumentOrderedMap::getAllElementsById): Added.

* dom/DocumentOrderedMap.h:

(WebCore::DocumentOrderedMap::MapEntry::MapEntry): Added.
(WebCore::DocumentOrderedMap::containsSingle): Updated to use new hash map.
(WebCore::DocumentOrderedMap::contains): Ditto.
(WebCore::DocumentOrderedMap::containsMultiple): Ditto.

* dom/Element.cpp:
(WebCore::Element::insertedInto): This function didn't add this element to window and document's name maps
if the element had already been inserted into a tree scope, and the current call was inserting an ancestor
of the tree scope into the document. We were exiting early per scope != treeScope().

Fixed the bug by splitting updateId into two functions updateIdForTreeScope and updateIdForDocument.
The former is called when this element is inserted into a new tree scope, and the latter is called when
this element is inserted into a HTML document even if it had already been inside some tree scope.

(WebCore::Element::removedFrom): This function didn't remove this element from tree scope's id maps if
the tree scope wasn't a document. Fixed the bug by simply checking that the removal happens beneath the
current tree scope.
(WebCore::Element::updateName):
(WebCore::Element::updateNameForTreeScope): Renamed from updateName.
(WebCore::Element::updateNameForDocument): Extracted from updateName.
(WebCore::Element::updateId):
(WebCore::Element::updateIdForTreeScope): Renamed from updateId.
(WebCore::Element::updateIdForDocument): Extracted from updateId.

* dom/Element.h:

* dom/SelectorQuery.cpp:
(WebCore::SelectorDataList::canUseIdLookup): Refactored to return the id subselector instead of checking if
the first subselector happens to be matching an id.
(WebCore::SelectorDataList::execute): Use the subselector canUseIdLookup returned. Also make use of newly
added getAllElementsById when there are multiple matching elements for a given id.

* dom/SelectorQuery.h:

* dom/TreeScope.cpp:
(WebCore::TreeScope::getAllElementsById): Added.

* dom/TreeScope.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@150187 268f45cc-cd09-0410-ab3c-d52691b4dbfc