[Offline Pages] Add UMA to record final offline request status and loading failed error code.

chrome/browser/android/offline_pages/background_loader_offliner_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/android/offline_pages/background_loader_offliner.h"
 
 #include "base/bind.h"
 #include "base/run_loop.h"
 #include "base/test/histogram_tester.h"
 #include "base/test/scoped_mock_time_message_loop_task_runner.h"
@@ skipping 15 matching lines @@
 #include "net/base/net_errors.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace offline_pages {
 
 namespace {
 
 const int64_t kRequestId = 7;
 const GURL kHttpUrl("http://www.tunafish.com");
 const GURL kFileUrl("file://salmon.png");
-const ClientId kClientId("AsyncLoading", "88");
+const ClientId kClientId("async_loading", "88");
 const bool kUserRequested = true;
 
 // Mock OfflinePageModel for testing the SavePage calls
 class MockOfflinePageModel : public StubOfflinePageModel {
  public:
   MockOfflinePageModel() : mock_saving_(false) {}
   ~MockOfflinePageModel() override {}
 
   void SavePage(const SavePageParams& save_page_params,
                 std::unique_ptr<OfflinePageArchiver> archiver,
@@ skipping 367 matching lines @@
   EXPECT_TRUE(completion_callback_called());
   EXPECT_EQ(Offliner::RequestStatus::LOADING_FAILED, request_status());
 }
 
 TEST_F(BackgroundLoaderOfflinerTest, FailsOnErrorPage) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
                           kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, completion_callback(),
                                       progress_callback()));
-
   // Create handle with net error code.
   // Called after calling LoadAndSave so we have web_contents to work with.
   std::unique_ptr<content::NavigationHandle> handle(
       content::NavigationHandle::CreateNavigationHandleForTesting(
           kHttpUrl, offliner()->web_contents()->GetMainFrame(), true,
           net::Error::ERR_NAME_NOT_RESOLVED));
-  // Call DidFinishNavigation with handle that contains error.
-  offliner()->DidFinishNavigation(handle.get());
-  // NavigationHandle is always destroyed after finishing navigation.
+  // NavigationHandle destruction will trigger DidFinishNavigation code.
   handle.reset();
+  histograms().ExpectBucketCount(
+      "OfflinePages.Background.BackgroundLoadingFailedCode.async_loading",
+      105,  // ERR_NAME_NOT_RESOLVED
+      1);
   offliner()->DidStopLoading();
   PumpLoop();
 
   EXPECT_TRUE(completion_callback_called());
   EXPECT_EQ(Offliner::RequestStatus::LOADING_FAILED_NO_RETRY, request_status());
 }
 
 TEST_F(BackgroundLoaderOfflinerTest, NoNextOnInternetDisconnected) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
@@ skipping 32 matching lines @@
   model()->CompleteSavingAsSuccess();
   PumpLoop();
 
   EXPECT_TRUE(completion_callback_called());
   EXPECT_EQ(Offliner::RequestStatus::SAVED, request_status());
   EXPECT_FALSE(offliner()->is_loading());
   EXPECT_FALSE(SaveInProgress());
 }
 
 }  // namespace offline_pages