Remove workarounds for <rdar://problem/5386894> now that it's been fixed

Remove workarounds for <rdar://problem/5386894> now that it's been fixed

WebCore:

        Remove workarounds for <rdar://problem/5386894> now that it's been fixed

        Reviewed by Darin.

        Tests: fast/loader/local-svg-parsed-as-svg.svg
               fast/loader/local-xhtml-parsed-as-xhtml.xhtml

        * platform/network/cf/ResourceResponseCFNet.cpp:
        (WebCore::ResourceResponse::doUpdateResourceResponse): Removed hackish
        workaround.

LayoutTests:

        Tests to ensure that local .xhtml and .svg files end up being parsed as XHTML and SVG, respectively

        Reviewed by Darin.

        * fast/loader/local-svg-parsed-as-svg-expected.txt: Added.
        * fast/loader/local-svg-parsed-as-svg.svg: Added.
        * fast/loader/local-xhtml-parsed-as-xhtml-expected.txt: Added.
        * fast/loader/local-xhtml-parsed-as-xhtml.xhtml: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@25162 268f45cc-cd09-0410-ab3c-d52691b4dbfc