Clarify wording around blocking 3rd party cookies and add lab to block reading of 3rd party cookies

webkit/tools/test_shell/simple_resource_loader_bridge.cc

Index: webkit/tools/test_shell/simple_resource_loader_bridge.cc
diff --git a/webkit/tools/test_shell/simple_resource_loader_bridge.cc b/webkit/tools/test_shell/simple_resource_loader_bridge.cc
index 14171a4f0f7b12da373959c82e5a204b8c9f2d95..e0348ff12db73031653ee13dd959070230c3b30d 100644
--- a/webkit/tools/test_shell/simple_resource_loader_bridge.cc
+++ b/webkit/tools/test_shell/simple_resource_loader_bridge.cc
@@ -166,7 +166,7 @@ class IOThread : public base::Thread {
   void SetAcceptAllCookies(bool accept_all_cookies) {
     StaticCookiePolicy::Type policy_type = accept_all_cookies ?
         StaticCookiePolicy::ALLOW_ALL_COOKIES :
-        StaticCookiePolicy::BLOCK_THIRD_PARTY_COOKIES;
+        StaticCookiePolicy::BLOCK_SETTING_THIRD_PARTY_COOKIES;
     static_cast<StaticCookiePolicy*>(g_request_context->cookie_policy())->
         set_type(policy_type);
   }