Introduce ThreadTaskRunnerHandle::OverrideForTesting and TestMockTimeTaskRunner::ScopedContext.

chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc

Index: chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
diff --git a/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc b/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
index c9626478f5cdfd0a4854ed755e20cc60122392c0..eb27eb829280c7816444934b476ebaa6fece35b9 100644
--- a/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
+++ b/chrome/browser/android/offline_pages/recent_tab_helper_unittest.cc
@@ -4,12 +4,13 @@
 
 #include "chrome/browser/android/offline_pages/recent_tab_helper.h"
 
+#include <memory>
+
 #include "base/memory/ptr_util.h"
-#include "base/run_loop.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/test/scoped_feature_list.h"
-#include "base/test/test_mock_time_task_runner.h"
+#include "base/test/scoped_mock_time_message_loop_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/android/offline_pages/offline_page_model_factory.h"
 #include "chrome/browser/android/offline_pages/request_coordinator_factory.h"
@@ -43,14 +44,12 @@ class TestDelegate: public RecentTabHelper::Delegate {
 
   explicit TestDelegate(
       OfflinePageTestArchiver::Observer* observer,
-      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
       int tab_id,
       bool tab_id_result);
   ~TestDelegate() override {}
 
   std::unique_ptr<OfflinePageArchiver> CreatePageArchiver(
         content::WebContents* web_contents) override;
-  scoped_refptr<base::SingleThreadTaskRunner> GetTaskRunner() override;
     // There is no expectations that tab_id is always present.
   bool GetTabId(content::WebContents* web_contents, int* tab_id) override;
   bool IsLowEndDevice() override { return is_low_end_device_; }
@@ -66,7 +65,6 @@ class TestDelegate: public RecentTabHelper::Delegate {
 
  private:
   OfflinePageTestArchiver::Observer* observer_;  // observer owns this.
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   int tab_id_;
   bool tab_id_result_;
 
@@ -87,13 +85,14 @@ class RecentTabHelperTest
   ~RecentTabHelperTest() override {}
 
   void SetUp() override;
+  void TearDown() override;
   const std::vector<OfflinePageItem>& GetAllPages();
 
   void FailLoad(const GURL& url);
 
-  // Runs default thread.
+  // Runs main thread.
   void RunUntilIdle();
-  // Moves forward the snapshot controller's task runner.
+  // Advances main thread time to trigger the snapshot controller's timeouts.
   void FastForwardSnapshotController();
 
   // Navigates to the URL and commit as if it has been typed in the address bar.
@@ -121,10 +120,6 @@ class RecentTabHelperTest
     return nullptr;
   }
 
-  scoped_refptr<base::TestMockTimeTaskRunner>& task_runner() {
-    return task_runner_;
-  }
-
   size_t page_added_count() { return page_added_count_; }
   size_t model_removed_count() { return model_removed_count_; }
 
@@ -155,9 +150,15 @@ class RecentTabHelperTest
   size_t model_removed_count_;
   std::vector<OfflinePageItem> all_pages_;
   bool all_pages_needs_updating_;
-  scoped_refptr<base::TestMockTimeTaskRunner> task_runner_;
   base::test::ScopedFeatureList scoped_feature_list_;
 
+  // Mocks the RenderViewHostTestHarness' main thread runner. Needs to be delay
+  // initialized in SetUp() -- can't be a simple member -- since
+  // RenderViewHostTestHarness only initializes its main thread environment in
+  // its SetUp() :(.
+  std::unique_ptr<base::ScopedMockTimeMessageLoopTaskRunner>
+      mocked_main_runner_;
+
   base::WeakPtrFactory<RecentTabHelperTest> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RecentTabHelperTest);
@@ -165,11 +166,9 @@ class RecentTabHelperTest
 
 TestDelegate::TestDelegate(
     OfflinePageTestArchiver::Observer* observer,
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     int tab_id,
     bool tab_id_result)
     : observer_(observer),
-      task_runner_(task_runner),
       tab_id_(tab_id),
       tab_id_result_(tab_id_result) {
 }
@@ -183,10 +182,7 @@ std::unique_ptr<OfflinePageArchiver> TestDelegate::CreatePageArchiver(
   return std::move(archiver);
 }
 
-scoped_refptr<base::SingleThreadTaskRunner> TestDelegate::GetTaskRunner() {
-  return task_runner_;
-}
-  // There is no expectations that tab_id is always present.
+// There is no expectations that tab_id is always present.
 bool TestDelegate::GetTabId(content::WebContents* web_contents, int* tab_id) {
   *tab_id = tab_id_;
   return tab_id_result_;
@@ -199,12 +195,14 @@ RecentTabHelperTest::RecentTabHelperTest()
       page_added_count_(0),
       model_removed_count_(0),
       all_pages_needs_updating_(true),
-      task_runner_(new base::TestMockTimeTaskRunner),
       weak_ptr_factory_(this) {}
 
 void RecentTabHelperTest::SetUp() {
   ChromeRenderViewHostTestHarness::SetUp();
 
+  mocked_main_runner_ =
+      base::MakeUnique<base::ScopedMockTimeMessageLoopTaskRunner>();
+
   scoped_feature_list_.InitAndEnableFeature(kOffliningRecentPagesFeature);
   // Sets up the factories for testing.
   OfflinePageModelFactory::GetInstance()->SetTestingFactoryAndUse(
@@ -218,7 +216,7 @@ void RecentTabHelperTest::SetUp() {
   recent_tab_helper_ = RecentTabHelper::FromWebContents(web_contents());
 
   std::unique_ptr<TestDelegate> test_delegate(
-      new TestDelegate(this, task_runner(), kTabId, true));
+      new TestDelegate(this, kTabId, true));
   default_test_delegate_ = test_delegate.get();
   recent_tab_helper_->SetDelegate(std::move(test_delegate));
 
@@ -226,6 +224,11 @@ void RecentTabHelperTest::SetUp() {
   model_->AddObserver(this);
 }
 
+void RecentTabHelperTest::TearDown() {
+  mocked_main_runner_.reset();
+  ChromeRenderViewHostTestHarness::TearDown();
+}
+
 void RecentTabHelperTest::FailLoad(const GURL& url) {
   controller().LoadURL(url, content::Referrer(), ui::PAGE_TRANSITION_TYPED,
                        std::string());
@@ -252,12 +255,12 @@ void RecentTabHelperTest::OnGetAllPagesDone(
 }
 
 void RecentTabHelperTest::RunUntilIdle() {
-  base::RunLoop().RunUntilIdle();
+  (*mocked_main_runner_)->RunUntilIdle();
 }
 
 void RecentTabHelperTest::FastForwardSnapshotController() {
-  const size_t kLongDelayMs = 100*1000;
-  task_runner_->FastForwardBy(base::TimeDelta::FromMilliseconds(kLongDelayMs));
+  constexpr base::TimeDelta kLongDelay = base::TimeDelta::FromSeconds(100);
+  (*mocked_main_runner_)->FastForwardBy(kLongDelay);
 }
 
 void RecentTabHelperTest::NavigateAndCommitTyped(const GURL& url) {
@@ -289,7 +292,6 @@ TEST_F(RecentTabHelperTest, LastNCaptureAfterLoad) {
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   // Move the snapshot controller's time forward so it gets past timeouts.
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_TRUE(model()->is_loaded());
   EXPECT_EQ(0U, page_added_count());
   ASSERT_EQ(0U, GetAllPages().size());
@@ -319,7 +321,6 @@ TEST_F(RecentTabHelperTest, NoLastNCaptureIfTabHiddenTooEarlyInPageLoad) {
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   // Move the snapshot controller's time forward so it gets past timeouts.
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(0U, page_added_count());
   ASSERT_EQ(0U, GetAllPages().size());
 }
@@ -328,8 +329,8 @@ TEST_F(RecentTabHelperTest, NoLastNCaptureIfTabHiddenTooEarlyInPageLoad) {
 // ignored from both last_n and downloads.
 TEST_F(RecentTabHelperTest, NoTabIdNoCapture) {
   // Create delegate that returns 'false' as TabId retrieval result.
-  recent_tab_helper()->SetDelegate(base::MakeUnique<TestDelegate>(
-      this, task_runner(), kTabId, false));
+  recent_tab_helper()->SetDelegate(
+      base::MakeUnique<TestDelegate>(this, kTabId, false));
 
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
@@ -375,7 +376,6 @@ TEST_F(RecentTabHelperTest, TwoCapturesSamePageLoad) {
   // Set page loading state to the 1st snapshot-able stage. No capture so far.
   recent_tab_helper()->DocumentAvailableInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_TRUE(model()->is_loaded());
   EXPECT_EQ(0U, page_added_count());
 
@@ -392,7 +392,6 @@ TEST_F(RecentTabHelperTest, TwoCapturesSamePageLoad) {
   // capture should happen.
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
@@ -465,7 +464,6 @@ TEST_F(RecentTabHelperTest, TwoCapturesDifferentPageLoadsSameUrl) {
   NavigateAndCommitTyped(kTestPageUrl);
   recent_tab_helper()->DocumentAvailableInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
@@ -531,7 +529,6 @@ TEST_F(RecentTabHelperTest, TwoCapturesDifferentPageLoadsDifferentUrls) {
   NavigateAndCommitTyped(kTestPageUrlOther);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
@@ -642,14 +639,12 @@ TEST_F(RecentTabHelperTest, DownloadRequestEarlyInLoad) {
   const ClientId client_id = NewDownloadClientId();
   recent_tab_helper()->ObserveAndDownloadCurrentPage(client_id, 153L);
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_TRUE(model()->is_loaded());
   ASSERT_EQ(0U, GetAllPages().size());
 
   // Minimally load the page. First capture should occur.
   recent_tab_helper()->DocumentAvailableInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   ASSERT_EQ(1U, GetAllPages().size());
   const OfflinePageItem& early_page = GetAllPages()[0];
   EXPECT_EQ(kTestPageUrl, early_page.url);
@@ -659,7 +654,6 @@ TEST_F(RecentTabHelperTest, DownloadRequestEarlyInLoad) {
   // Fully load the page. A second capture should replace the first one.
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
@@ -676,7 +670,6 @@ TEST_F(RecentTabHelperTest, DownloadRequestLaterInLoad) {
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentAvailableInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_TRUE(model()->is_loaded());
   ASSERT_EQ(0U, GetAllPages().size());
 
@@ -691,7 +684,6 @@ TEST_F(RecentTabHelperTest, DownloadRequestLaterInLoad) {
 
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(2U, page_added_count());
   EXPECT_EQ(1U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());
@@ -703,7 +695,6 @@ TEST_F(RecentTabHelperTest, DownloadRequestAfterFullyLoad) {
   NavigateAndCommit(kTestPageUrl);
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_TRUE(model()->is_loaded());
   ASSERT_EQ(0U, GetAllPages().size());
 
@@ -793,7 +784,6 @@ TEST_F(RecentTabHelperTest, OverlappingDownloadRequestsAreIgnored) {
   // Finish loading the page. Only the first request should be executed.
   recent_tab_helper()->DocumentOnLoadCompletedInMainFrame();
   FastForwardSnapshotController();
-  RunUntilIdle();
   EXPECT_EQ(1U, page_added_count());
   EXPECT_EQ(0U, model_removed_count());
   ASSERT_EQ(1U, GetAllPages().size());