Reviewed by Antti Koivisto.

Simplify SVGElement construction by making them opt in to custom style resolve callbacks
by default, and removing the ability to pass a custom ConstructionType to some subclass
constructors.

* dom/Node.h:

    Add HasCustomStyleResolveCallbacksFlag to the CreateSVGElement mask.

* svg/SVGElement.cpp:
(WebCore::SVGElement::SVGElement):
* svg/SVGElement.h:
* svg/SVGGElement.cpp:
(WebCore::SVGGElement::SVGGElement):
* svg/SVGGElement.h:
* svg/SVGGraphicsElement.cpp:
(WebCore::SVGGraphicsElement::SVGGraphicsElement):
* svg/SVGGraphicsElement.h:
* svg/SVGImageElement.cpp:
(WebCore::SVGImageElement::SVGImageElement):
* svg/SVGStyledElement.cpp:
(WebCore::SVGStyledElement::SVGStyledElement):
* svg/SVGStyledElement.h:

    Remove calls to setHasCustomStyleResolveCallbacks() in SVGElement and subclasses.
    Also remove unnecessary ConstructionType argument from subclasses since nobody
    overrides it and everyone just uses CreateSVGElement.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154414 268f45cc-cd09-0410-ab3c-d52691b4dbfc