https://bugs.webkit.org/show_bug.cgi?id=62459

Previous policy only allowed favicons for pages whose protocol was part of HTTP family.
Changed that to allow to any url that's not empty and whose protocol is not "about".
Also added this check where it attempts to start loading the favicon, so it can avoid
wasting time downloading a resource that won't be stored and won't be used.

Patch by Rafael Brandao <rafael.lobo@openbossa.org> on 2011-07-21
Reviewed by Adam Barth.

Test: manual-tests/resources/favicon-loads-for-local-files.html

* loader/icon/IconController.cpp:
(WebCore::IconController::startLoader): Added check to avoid to request a favicon
when there's no way to store it.

* loader/icon/IconDatabase.cpp:
(WebCore::IconDatabase::documentCanHaveIcon): Renamed function "pageCanHaveIcon"
to reflect better which url we're handling.

(WebCore::IconDatabase::synchronousIconForPageURL): Ditto.
(WebCore::IconDatabase::synchronousIconURLForPageURL): Ditto.
(WebCore::IconDatabase::retainIconForPageURL): Ditto.
(WebCore::IconDatabase::releaseIconForPageURL): Ditto.
(WebCore::IconDatabase::setIconURLForPageURL): Ditto.
(WebCore::IconDatabase::getOrCreatePageURLRecord): Ditto.
(WebCore::IconDatabase::importIconURLForPageURL): Ditto.
(WebCore::IconDatabase::performURLImport): Ditto.
* loader/icon/IconDatabase.h:
* loader/icon/IconDatabaseBase.h:
(WebCore::IconDatabaseBase::documentCanHaveIcon): Added it as virtual to replace its
default behavior of not allowing favicons when we have IconDatabase enabled.

* manual-tests/resources/favicon-loads-for-local-files.html: Added.
* manual-tests/resources/favicon.png: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@91540 268f45cc-cd09-0410-ab3c-d52691b4dbfc