Recursion handling cancelled authentication challenges in NetworkProcess
<rdar://problem/13024541> and https://bugs.webkit.org/show_bug.cgi?id=107702

Reviewed by Alexey Proskuryakov.

Source/WebCore:

* WebCore.exp.in:

Source/WebKit2:

This turned in to both a bug fix with authentication and a minimal refactoring of NetworkResourceLoader.

- Rename ::stop to ::resourceHandleStopped
- Move all cleanup code to ::resourceHandleStopped
- Schedule a resourceHandleStopped call when an authentication cancellation occurs
- Tell the WebResourceLoader to cancel when an authentication cancellation occurs

* NetworkProcess/NetworkResourceLoader.cpp:
(WebKit::NetworkResourceLoader::~NetworkResourceLoader):
(WebKit::NetworkResourceLoader::start):
(WebKit::NetworkResourceLoader::performStops):
(WebKit::NetworkResourceLoader::resourceHandleStopped):
(WebKit::NetworkResourceLoader::didFail):
(WebKit::NetworkResourceLoader::receivedAuthenticationCancellation):
* NetworkProcess/NetworkResourceLoader.h:

* WebProcess/Network/WebResourceLoader.cpp:
(WebKit::WebResourceLoader::cancelResourceLoader):
* WebProcess/Network/WebResourceLoader.h:
* WebProcess/Network/WebResourceLoader.messages.in:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140572 268f45cc-cd09-0410-ab3c-d52691b4dbfc