Teach URLRequest about initiator checks for First-Party-Only cookies.

content/browser/appcache/appcache_update_job.cc

Index: content/browser/appcache/appcache_update_job.cc
diff --git a/content/browser/appcache/appcache_update_job.cc b/content/browser/appcache/appcache_update_job.cc
index a3c8476cf9de32c29dd94532acd6c4007e64ba85..b6ab3fb7318e58ac67bb694bae21d693118ed086 100644
--- a/content/browser/appcache/appcache_update_job.cc
+++ b/content/browser/appcache/appcache_update_job.cc
@@ -20,6 +20,7 @@
 #include "net/http/http_request_headers.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/url_request_context.h"
+#include "url/origin.h"
 
 namespace content {
 
@@ -163,6 +164,7 @@ AppCacheUpdateJob::URLFetcher::~URLFetcher() {
 
 void AppCacheUpdateJob::URLFetcher::Start() {
   request_->set_first_party_for_cookies(job_->manifest_url_);
+  request_->set_initiator(url::Origin(job_->manifest_url_));
   if (fetch_type_ == MANIFEST_FETCH && job_->doing_full_update_check_)
     request_->SetLoadFlags(request_->load_flags() | net::LOAD_BYPASS_CACHE);
   else if (existing_response_headers_.get())