Fill in the NIK in a test factory used in network_context_unittest.cc

This will fix some broken tests
(e.g. NetworkContextMockHostTest.CustomProxyConfigHeadersAddedBeforeCache)
when SplitCache feature is enabled.

Also fixed another test expectation to make it work when SplitCache is
enabled.

Bug: 1009597
Change-Id: Iff8e67e7791f4458941e25eeb4c29364057fabf9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1844474Reviewed-by: Matt Menke <mmenke@chromium.org>
Reviewed-by: Shivani Sharma <shivanisha@chromium.org>
Commit-Queue: Yao Xiao <yaoxia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703934}

services/network/network_context_unittest.cc

@@ -213,6 +213,9 @@ std::unique_ptr<TestURLLoaderClient> FetchRequest(
   auto params = mojom::URLLoaderFactoryParams::New();
   params->process_id = process_id;
   params->is_corb_enabled = false;
+  params->network_isolation_key =
+      net::NetworkIsolationKey(url::Origin::Create(GURL("https://abc.com")),
+                               url::Origin::Create(GURL("https://xyz.com")));
   network_context->CreateURLLoaderFactory(mojo::MakeRequest(&loader_factory),
                                           std::move(params));
 
@@ -1365,10 +1368,14 @@ TEST_F(NetworkContextTest, NotifyExternalCacheHit) {
     network_context->NotifyExternalCacheHit(test_url, test_url.scheme(), key);
     EXPECT_EQ(i + 1, mock_cache.disk_cache()->GetExternalCacheHits().size());
 
-    // Potentially a brittle check as the value sent to disk_cache is a "key."
-    // This key just happens to be the same as the GURL from the test input.
-    // So if this breaks check HttpCache::GenerateCacheKey() for changes.
-    EXPECT_EQ(test_url, mock_cache.disk_cache()->GetExternalCacheHits().back());
+    // Note: if this breaks check HttpCache::GenerateCacheKey() for changes.
+    std::string expected_key_prefix =
+        base::FeatureList::IsEnabled(
+            net::features::kSplitCacheByNetworkIsolationKey)
+            ? base::StrCat({"_dk_", key.ToString(), " "})
+            : "";
+    EXPECT_EQ(expected_key_prefix + test_url.spec(),
+              mock_cache.disk_cache()->GetExternalCacheHits().back());
   }
 }