Attempt to address libxml crash.

BUG=129930
Review URL: https://chromiumcodereview.appspot.com/10458051

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@142822 0039d316-1c4b-4281-b951-d872f2087c98
__xmlParserInputBufferCreateFilenameValue(void) {
    if (IS_MAIN_THREAD)
	return (&xmlParserInputBufferCreateFilenameValue);
    else
	return (&xmlGetGlobalState()->xmlParserInputBufferCreateFilenameValue);
}

__xmlParserInputBufferCreateFilenameValue(void) {
    if (IS_MAIN_THREAD)
	return (&xmlParserInputBufferCreateFilenameValue);
    else
	return (&xmlGetGlobalState()->xmlParserInputBufferCreateFilenameValue);
}
