Factor HTMLTokenScanner out of HTMLPreloadScanner
https://bugs.webkit.org/show_bug.cgi?id=109754

Reviewed by Eric Seidel.

This patch is just a mechanical separation of the per-token "scanning"
logic from HTMLPreloadScanner into a separate class.
HTMLPreloadScanner's job is now to keep track of the input stream and
to pump the tokenizer.

This factorization class will let us use HTMLTokenScanner on the
background thread (once we finish making it thread-safe). In a follow
up patch, I'll move HTMLTokenScanner to its own file.

* html/parser/HTMLPreloadScanner.cpp:
(WebCore::HTMLTokenScanner::HTMLTokenScanner):
(WebCore::HTMLTokenScanner::~HTMLTokenScanner):
(WebCore::HTMLTokenScanner::processPossibleTemplateTag):
(WebCore::HTMLTokenScanner::processPossibleStyleTag):
(WebCore::HTMLTokenScanner::processPossibleBaseTag):
(WebCore::HTMLTokenScanner::scan):
(WebCore::HTMLPreloadScanner::HTMLPreloadScanner):
(WebCore):
(WebCore::HTMLPreloadScanner::~HTMLPreloadScanner):
(WebCore::HTMLPreloadScanner::appendToEnd):
(WebCore::HTMLPreloadScanner::scan):
* html/parser/HTMLPreloadScanner.h:
(HTMLTokenScanner):
(WebCore::HTMLTokenScanner::setPredictedBaseElementURL):
(HTMLPreloadScanner):
(WebCore):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@142822 268f45cc-cd09-0410-ab3c-d52691b4dbfc