LoadingPredictor: Use NetworkIsolationKey for omnibox preconnects.

Bug: 966896
Change-Id: I3487a844817f307ebeb1a830f27910fe21dea635
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1721433
Commit-Queue: Matt Menke <mmenke@chromium.org>
Reviewed-by: Alex Ilin <alexilin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#682776}

chrome/browser/predictors/loading_predictor.cc

@@ -235,7 +235,10 @@ void LoadingPredictor::HandleOmniboxHint(const GURL& url, bool preconnectable) {
     if (is_new_origin || now - last_omnibox_preconnect_time_ >=
                              kMinDelayBetweenPreconnectRequests) {
       last_omnibox_preconnect_time_ = now;
-      preconnect_manager()->StartPreconnectUrl(url, true);
+      // Not to be confused with |origin|.
+      url::Origin url_origin = url::Origin::Create(url);
+      preconnect_manager()->StartPreconnectUrl(
+          url, true, net::NetworkIsolationKey(url_origin, url_origin));
     }
     return;
   }

chrome/browser/predictors/loading_predictor_unittest.cc

@@ -312,9 +312,10 @@ TEST_F(LoadingPredictorTest, TestDontPredictOmniboxHints) {
 
 TEST_F(LoadingPredictorPreconnectTest, TestHandleOmniboxHint) {
   const GURL preconnect_suggestion = GURL("http://search.com/kittens");
-  EXPECT_CALL(*mock_preconnect_manager_,
-              StartPreconnectUrl(preconnect_suggestion, true,
-                                 net::NetworkIsolationKey()));
+  EXPECT_CALL(
+      *mock_preconnect_manager_,
+      StartPreconnectUrl(preconnect_suggestion, true,
+                         CreateNetworkIsolationKey(preconnect_suggestion)));
   predictor_->PrepareForPageLoad(preconnect_suggestion, HintOrigin::OMNIBOX,
                                  true);
   // The second suggestion for the same host should be filtered out.