Support for multiple <link rel="icon"> favicon elements.

Support for multiple <link rel="icon"> favicon elements.
https://bugs.webkit.org/show_bug.cgi?id=65564

Patch by Rachel Blum <groby@chromium.org> on 2011-09-20
Reviewed by Darin Fisher.

No tests - purely an API change. (And API is not exposed to LayoutTests)

* dom/Document.cpp:
(WebCore::Document::iconURLs):
(WebCore::Document::addIconURL):
* dom/Document.h:
* dom/IconURL.cpp:
(WebCore::toIconIndex):
* dom/IconURL.h:
(WebCore::IconURL::IconURL):
* html/HTMLLinkElement.cpp:
(WebCore::HTMLLinkElement::process):
* loader/LinkLoader.cpp:
(WebCore::LinkLoader::loadLink):
* loader/LinkLoader.h:
* loader/icon/IconController.cpp:
(WebCore::IconController::urlsForTypes):
(WebCore::IconController::appendToIconURLs):
(WebCore::IconController::defaultURL):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@95593 268f45cc-cd09-0410-ab3c-d52691b4dbfc