http://bugs.webkit.org/show_bug.cgi?id=15555
        XMLHttpRequest does not support charset "x-user-defined", which can
        facilitate loading of binary data

        Test: http/tests/xmlhttprequest/binary-x-user-defined.html

        * WebCore.pro:
        * WebCore.vcproj/WebCore.vcproj:
        * WebCore.xcodeproj/project.pbxproj:
        * platform/TextCodecUserDefined.cpp: Added.
        (WebCore::TextCodecUserDefined::registerEncodingNames):
        (WebCore::newStreamingTextDecoderUserDefined):
        (WebCore::TextCodecUserDefined::registerCodecs):
        (WebCore::TextCodecUserDefined::decode):
        (WebCore::encodeComplexUserDefined):
        (WebCore::TextCodecUserDefined::encode):
        * platform/TextCodecUserDefined.h: Added.
        * platform/TextEncodingRegistry.cpp:
        (WebCore::buildBaseTextCodecMaps):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@27145 268f45cc-cd09-0410-ab3c-d52691b4dbfc