Add cross origin to Blink-driven preconnect

chrome/browser/net/preconnect.cc

Index: chrome/browser/net/preconnect.cc
diff --git a/chrome/browser/net/preconnect.cc b/chrome/browser/net/preconnect.cc
index 01cadcce243593d28125112e78316302de3cdd94..7b561de5e53519e83cf465146f9383e71de1489f 100644
--- a/chrome/browser/net/preconnect.cc
+++ b/chrome/browser/net/preconnect.cc
@@ -8,6 +8,7 @@
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "content/public/browser/browser_thread.h"
+#include "net/base/load_flags.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_request_info.h"
 #include "net/http/http_stream_factory.h"
@@ -33,7 +34,7 @@ void PreconnectOnUIThread(
       BrowserThread::IO,
       FROM_HERE,
       base::Bind(&PreconnectOnIOThread, url, first_party_for_cookies,
-                 motivation, count, make_scoped_refptr(getter)));
+                 motivation, count, make_scoped_refptr(getter), false));
   return;
 }
 
@@ -43,7 +44,8 @@ void PreconnectOnIOThread(
     const GURL& first_party_for_cookies,
     UrlInfo::ResolutionMotivation motivation,
     int count,
-    net::URLRequestContextGetter* getter) {
+    net::URLRequestContextGetter* getter,
+    bool is_credentials_flag_set) {
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
     LOG(DFATAL) << "This must be run only on the IO thread.";
     return;
@@ -68,7 +70,8 @@ void PreconnectOnIOThread(
                                        user_agent);
 
   net::NetworkDelegate* delegate = context->network_delegate();
-  if (delegate->CanEnablePrivacyMode(url, first_party_for_cookies))
+  if (delegate->CanEnablePrivacyMode(url, first_party_for_cookies)
+    || !is_credentials_flag_set)

[Ryan Sleevi, 2015/06/11 22:20:15]

To be clear: You're going to need to dig in to why this doesn't work for your
test, what the root cause is, and what may need to change.

Using this bool to set privacy_mode_enabled, even if it causes the correct
behaviour, isn't consistent with the API contract. You shouldn't be setting this
yourself - it's //net's responsibility to do that based on the cookie settings
and load flags (fwiw, it's here -
https://code.google.com/p/chromium/codesearch#chromium/src/net/url_request/ur...
)

If I were a betting man, it's because HttpStreamFactory::PreconnectStreams
likely isn't aware of the UrlRequestHttpJob (which builds atop the
HttpStreamFactory, and is thus a higher layer), and as a result, is bypassing
the code I just linked. Because of this, even though you 'should' be in privacy
mode, you're not.

The existing lines of this file (lines 71/72) of this are weird, because they're
violating the layering of the UrlRequestHttpInfo.

I'll have to think about this and talk it over with some folks to see what the
thoughts are. It's possible we may just say "whatever" and let this code
through, or it may be that we say "Push this down a layer first" as part of the
'leave the code cleaner'.

My own instinct is that if we're going to properly enshrine things, what we
probably want to do is push this logic into PreconnectStreams (really, the
HttpStreamFactory), which means that it needs to touch the NetworkDelegate (it
already can), and would need both |url| and |first_party_for_cookies| URLs
pushed into it (the same as UrlRequestHttpJob does, ish).

Just making sure to document the thinking here

     request_info.privacy_mode = net::PRIVACY_MODE_ENABLED;
 
   // It almost doesn't matter whether we use net::LOWEST or net::HIGHEST