[Offline Pages] Turn Offliner::Cancel into an async operation to resolve conflicting assumptions

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/threading/thread_task_runner_handle.h"
@@ skipping 114 matching lines @@
   BackgroundLoaderOfflinerTest();
   ~BackgroundLoaderOfflinerTest() override;
 
   void SetUp() override;
 
   TestBackgroundLoaderOffliner* offliner() const { return offliner_.get(); }
   Offliner::CompletionCallback const callback() {
     return base::Bind(&BackgroundLoaderOfflinerTest::OnCompletion,
                       base::Unretained(this));
   }
+  Offliner::CancelCallback const cancel_callback() {
+    return base::Bind(&BackgroundLoaderOfflinerTest::OnCancel,
+                      base::Unretained(this));
+  }
   Profile* profile() { return &profile_; }
   bool completion_callback_called() { return completion_callback_called_; }
   Offliner::RequestStatus request_status() { return request_status_; }
+  bool cancel_callback_called() { return cancel_callback_called_; }
   bool SaveInProgress() const { return model_->mock_saving(); }
   MockOfflinePageModel* model() const { return model_; }
   const base::HistogramTester& histograms() const { return histogram_tester_; }
 
   void CompleteLoading() {
     // For some reason, setting loading to True will call DidStopLoading
     // on the observers.
     offliner()->web_contents_tester()->TestSetIsLoading(true);
   }
 
  private:
   void OnCompletion(const SavePageRequest& request,
                     Offliner::RequestStatus status);
+  void OnCancel(int64_t offline_id);
   content::TestBrowserThreadBundle thread_bundle_;
   TestingProfile profile_;
   std::unique_ptr<TestBackgroundLoaderOffliner> offliner_;
   MockOfflinePageModel* model_;
   bool completion_callback_called_;
+  bool cancel_callback_called_;
   Offliner::RequestStatus request_status_;
   base::HistogramTester histogram_tester_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundLoaderOfflinerTest);
 };
 
 BackgroundLoaderOfflinerTest::BackgroundLoaderOfflinerTest()
     : thread_bundle_(content::TestBrowserThreadBundle::IO_MAINLOOP),
       completion_callback_called_(false),
+      cancel_callback_called_(false),
       request_status_(Offliner::RequestStatus::UNKNOWN) {}
 
 BackgroundLoaderOfflinerTest::~BackgroundLoaderOfflinerTest() {}
 
 void BackgroundLoaderOfflinerTest::SetUp() {
   model_ = new MockOfflinePageModel();
   offliner_.reset(new TestBackgroundLoaderOffliner(profile(), nullptr, model_));
 }
 
 void BackgroundLoaderOfflinerTest::OnCompletion(
     const SavePageRequest& request,
     Offliner::RequestStatus status) {
   DCHECK(!completion_callback_called_);  // Expect 1 callback per request.
   completion_callback_called_ = true;
   request_status_ = status;
 }
 
+void BackgroundLoaderOfflinerTest::OnCancel(int64_t offline_id) {
+  DCHECK(!cancel_callback_called_);
+  cancel_callback_called_ = true;
+}
+
 TEST_F(BackgroundLoaderOfflinerTest,
        LoadAndSaveBlockThirdPartyCookiesForCustomTabs) {
   base::Time creation_time = base::Time::Now();
   ClientId custom_tabs_client_id("custom_tabs", "88");
   SavePageRequest request(kRequestId, kHttpUrl, custom_tabs_client_id,
                           creation_time, kUserRequested);
 
   profile()->GetPrefs()->SetBoolean(prefs::kBlockThirdPartyCookies, true);
   EXPECT_FALSE(offliner()->LoadAndSave(request, callback()));
   histograms().ExpectBucketCount(
@@ skipping 49 matching lines @@
   EXPECT_FALSE(completion_callback_called());
   EXPECT_TRUE(SaveInProgress());
   EXPECT_EQ(Offliner::RequestStatus::UNKNOWN, request_status());
 }
 
 TEST_F(BackgroundLoaderOfflinerTest, CancelWhenLoading) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
                           kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
-  offliner()->Cancel();
+  offliner()->Cancel(cancel_callback());
+  PumpLoop();
+  EXPECT_TRUE(cancel_callback_called());
   EXPECT_FALSE(offliner()->is_loading());  // Offliner reset.
 }
 
 TEST_F(BackgroundLoaderOfflinerTest, CancelWhenLoaded) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
                           kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
   CompleteLoading();
   PumpLoop();
-  offliner()->Cancel();
+  offliner()->Cancel(cancel_callback());
+  PumpLoop();
 
   // Subsequent save callback cause no crash.
   model()->CompleteSavingAsArchiveCreationFailed();
   PumpLoop();
+  EXPECT_TRUE(cancel_callback_called());
   EXPECT_FALSE(completion_callback_called());
   EXPECT_FALSE(SaveInProgress());
   EXPECT_FALSE(offliner()->is_loading());  // Offliner reset.
 }
 
 TEST_F(BackgroundLoaderOfflinerTest, LoadedButSaveFails) {
   base::Time creation_time = base::Time::Now();
   SavePageRequest request(kRequestId, kHttpUrl, kClientId, creation_time,
                           kUserRequested);
   EXPECT_TRUE(offliner()->LoadAndSave(request, callback()));
@@ skipping 85 matching lines @@
   // NavigationHandle is always destroyed after finishing navigation.
   handle.reset();
   offliner()->DidStopLoading();
   PumpLoop();
 
   EXPECT_TRUE(completion_callback_called());
   EXPECT_EQ(Offliner::RequestStatus::LOADING_FAILED_NO_RETRY, request_status());
 }
 
 }  // namespace offline_pages