Add support to previews/ for Server LoFi and LitePages

components/previews/core/previews_io_data_unittest.cc

Index: components/previews/core/previews_io_data_unittest.cc
diff --git a/components/previews/core/previews_io_data_unittest.cc b/components/previews/core/previews_io_data_unittest.cc
index 604cb1aa0603f64b1be6a683c7c5605a9bd583b9..1b535c175f78415ee30ec1fc9b57e642eb76b050 100644
--- a/components/previews/core/previews_io_data_unittest.cc
+++ b/components/previews/core/previews_io_data_unittest.cc
@@ -46,7 +46,10 @@ namespace {
 // chrome/browser/previews/previews_service.cc and into the previews/ component.
 bool IsPreviewFieldTrialEnabled(PreviewsType type) {
   switch (type) {
+    // Use the offline field trial to simulate LoFi and LitePages being enabled.

[tbansal1, 2017/05/02 21:49:31]

Is it possible to expand on this comment a bit? This is a bit confusing (why is
LoFi/Lite using offline field trial).

[RyanSturm, 2017/05/02 22:57:19]

Done. I removed sclittle's comment as it makes little sense to try to remove a
layering abstraction in test. Using the field trials is syntactically easy, but
this check could be replaced with any other bool that controls the flow of this
method for the purpose of the test.

     case PreviewsType::OFFLINE:
+    case PreviewsType::LITE_PAGE:
+    case PreviewsType::SERVER_LOFI:
       return params::IsOfflinePreviewsEnabled();
     case PreviewsType::CLIENT_LOFI:
       return params::IsClientLoFiEnabled();
@@ -273,6 +276,29 @@ TEST_F(PreviewsIODataTest, TestDisallowOfflineWhenNetworkQualityUnavailable) {
       1);
 }
 
+TEST_F(PreviewsIODataTest, TestAllowLoFiLitePageWhenNetworkQualityFast) {
+  // LoFi and LitePage check NQE on their own.
+  InitializeUIService();
+  CreateFieldTrialWithParams("ClientSidePreviews", "Enabled",
+                             {{"show_offline_pages", "true"},
+                              {"max_allowed_effective_connection_type", "2G"}});
+
+  network_quality_estimator()->set_effective_connection_type(
+      net::EFFECTIVE_CONNECTION_TYPE_3G);
+
+  base::HistogramTester histogram_tester;
+  EXPECT_TRUE(io_data()->ShouldAllowPreview(*CreateRequest(),
+                                            PreviewsType::SERVER_LOFI));
+  EXPECT_TRUE(
+      io_data()->ShouldAllowPreview(*CreateRequest(), PreviewsType::LITE_PAGE));
+  histogram_tester.ExpectUniqueSample(
+      "Previews.EligibilityReason.ServerLoFi",
+      static_cast<int>(PreviewsEligibilityReason::ALLOWED), 1);
+  histogram_tester.ExpectUniqueSample(
+      "Previews.EligibilityReason.LitePage",
+      static_cast<int>(PreviewsEligibilityReason::ALLOWED), 1);
+}
+
 TEST_F(PreviewsIODataTest, TestDisallowOfflineWhenNetworkQualityFast) {
   InitializeUIService();
   CreateFieldTrialWithParams("ClientSidePreviews", "Enabled",
@@ -306,9 +332,7 @@ TEST_F(PreviewsIODataTest, TestDisallowOfflineOnReload) {
   EXPECT_FALSE(io_data()->ShouldAllowPreview(*request, PreviewsType::OFFLINE));
   histogram_tester.ExpectUniqueSample(
       "Previews.EligibilityReason.Offline",
-      static_cast<int>(
-          PreviewsEligibilityReason::RELOAD_DISALLOWED_FOR_OFFLINE),
-      1);
+      static_cast<int>(PreviewsEligibilityReason::RELOAD_DISALLOWED), 1);
 }
 
 TEST_F(PreviewsIODataTest, TestAllowOffline) {