Reviewed by Sam Weinig.

        Move all member variables from MappedAttribute to Attribute.
        https://bugs.webkit.org/show_bug.cgi?id=39336
        <rdar://problem/8000853>

        This saves one word because we no longer have any virtual member functions in Attribute, and
        thus no vtable pointer.
        
        I plan to remove MappedAttribute altogether in a subsequent commit.

        * Android.mk:
        * GNUmakefile.am:
        * WebCore.gypi:
        * WebCore.pro:
        * WebCore.vcproj/WebCore.vcproj:
        * WebCore.xcodeproj/project.pbxproj:
        * css/CSSStyleSelector.cpp:
        (WebCore::CSSStyleSelector::styleForElement):
        * dom/Attribute.cpp:
        (WebCore::Attribute::clone):
        * dom/Attribute.h:
        (WebCore::Attribute::create):
        (WebCore::Attribute::style):
        (WebCore::Attribute::decl):
        (WebCore::Attribute::setDecl):
        (WebCore::Attribute::isMappedAttribute):
        (WebCore::Attribute::Attribute):
        * dom/MappedAttribute.cpp: Removed.
        * dom/MappedAttribute.h:
        (WebCore::MappedAttribute::create):
        (WebCore::MappedAttribute::MappedAttribute):
        (WebCore::toMappedAttribute):
        * dom/NamedMappedAttrMap.cpp:
        (WebCore::NamedMappedAttrMap::declCount):
        (WebCore::NamedMappedAttrMap::mapsEquivalent):
        * dom/StyledElement.cpp:
        (WebCore::StyledElement::attributeChanged):
        * svg/SVGSVGElement.cpp:
        (WebCore::updateCSSForAttribute):
        * svg/SVGStyledElement.cpp:
        (WebCore::SVGStyledElement::getPresentationAttribute):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@59724 268f45cc-cd09-0410-ab3c-d52691b4dbfc