Remove SVGUseElement.instanceRoot and all tests that depend on it

Remove SVGUseElement.instanceRoot and all tests that depend on it
https://bugs.webkit.org/show_bug.cgi?id=141025

Reviewed by Anders Carlsson.

Source/WebCore:

* svg/SVGUseElement.cpp:
(WebCore::SVGUseElement::instanceRoot): Deleted.
* svg/SVGUseElement.h: Removed instanceRoot.
* svg/SVGUseElement.idl: Ditto.

LayoutTests:

* platform/gtk/TestExpectations: Removed expected failure for now-removed test.
* platform/ios-simulator-wk2/TestExpectations: Ditto.
* platform/mac/TestExpectations: Ditto.

* platform/gtk/svg/custom/use-elementInstance-event-target-expected.png: Removed.
* platform/gtk/svg/custom/use-elementInstance-event-target-expected.txt: Removed.
* platform/gtk/svg/custom/use-elementInstance-methods-expected.png: Removed.
* platform/gtk/svg/custom/use-elementInstance-methods-expected.txt: Removed.
* platform/ios-sim-deprecated/svg/custom/use-elementInstance-event-target-expected.txt: Removed.
* platform/ios-sim-deprecated/svg/custom/use-elementInstance-methods-expected.txt: Removed.
* platform/ios-simulator/svg/custom/use-elementInstance-event-target-expected.txt: Removed.
* platform/ios-simulator/svg/custom/use-elementInstance-methods-expected.txt: Removed.
* platform/mac-mountainlion/svg/custom/use-elementInstance-event-target-expected.txt: Removed.
* platform/mac-mountainlion/svg/custom/use-elementInstance-methods-expected.txt: Removed.
* platform/mac/svg/custom/use-elementInstance-event-target-expected.png: Removed.
* platform/mac/svg/custom/use-elementInstance-event-target-expected.txt: Removed.
* platform/mac/svg/custom/use-elementInstance-methods-expected.png: Removed.
* platform/mac/svg/custom/use-elementInstance-methods-expected.txt: Removed.
* svg/custom/element-instance-held-by-js-crash-expected.txt: Removed.
* svg/custom/element-instance-held-by-js-crash.svg: Removed.
* svg/custom/resources/use-instanceRoot-event-bubbling.js: Find element by id instead
of using use.instanceRoot.correspondingElement.
* svg/custom/resources/use-instanceRoot-event-listeners.js: Removed.
* svg/custom/use-crash-using-children-before-destroy.svg: Removed a line of code that
got at the instanceRoot. It's possible this test no longer has value, and if so, then
we could later delete it, but it does no harm.
* svg/custom/use-elementInstance-event-target.svg: Removed.
* svg/custom/use-elementInstance-methods.svg: Removed.
* svg/custom/use-instanceRoot-as-event-target-expected.txt: Removed.
* svg/custom/use-instanceRoot-as-event-target.xhtml: Removed.
* svg/custom/use-instanceRoot-event-listener-liveness-expected.txt: Removed.
* svg/custom/use-instanceRoot-event-listener-liveness.xhtml: Removed.
* svg/custom/use-instanceRoot-event-listeners-expected.txt: Removed.
* svg/custom/use-instanceRoot-event-listeners.xhtml: Removed.
* svg/custom/use-instanceRoot-modifications.svg: Removed the part of this that involved
the instanceRoot property. It's possible this test now has reduced value, and if so, we
could later delete it but it does no harm.
* svg/custom/use-instanceRoot-with-use-removed.svg: Removed the use of instanceRoot
and correspondingUseElement. Not certain this remains a useful test. Also converted line
endings to LF instead of CRLF.
* svg/custom/use-listener-append-crash.html: Get elements by id instead of instanceRoot.
* svg/custom/use-modify-target-container.svg: Ditto.
* svg/custom/use-modify-target-symbol.svg: Ditto.
* svg/custom/use-on-use-with-child-expected.txt: Updated since we don't dump an instance
tree any more.
* svg/custom/use-on-use-with-child.svg: Removed the part about dumping the instance tree,
and added in the part about dragging to make sure it doesn't crash.
* svg/dom/use-transform.svg: Get element by id instead of instanceRoot.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@179391 268f45cc-cd09-0410-ab3c-d52691b4dbfc