Track Previews infobar dismissals due to tab closure

chrome/browser/previews/previews_infobar_delegate_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/previews/previews_infobar_delegate.h"
 
 #include <memory>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 205 matching lines @@
   EXPECT_EQ(0U, infobar_service()->infobar_count());
 
   tester.ExpectBucketCount(kUMAPreviewsInfoBarActionLoFi,
                            PreviewsInfoBarDelegate::INFOBAR_DISMISSED_BY_USER,
                            1);
   EXPECT_EQ(0, drp_test_context_->pref_service()->GetInteger(
                    data_reduction_proxy::prefs::kLoFiLoadImagesPerSession));
   EXPECT_FALSE(user_opt_out_.value());
 }
 
+TEST_F(PreviewsInfoBarDelegateUnitTest, InfobarTestTabClosedDismissal) {
+  base::HistogramTester tester;
+
+  CreateInfoBar(PreviewsInfoBarDelegate::LOFI, true /* is_data_saver_user */);
+
+  // Delete the infobar without any other infobar actions.
+  infobar_service()->infobar_at(0)->RemoveSelf();
+  EXPECT_EQ(0U, infobar_service()->infobar_count());
+
+  tester.ExpectBucketCount(
+      kUMAPreviewsInfoBarActionLoFi,
+      PreviewsInfoBarDelegate::INFOBAR_DISMISSED_BY_TAB_CLOSURE, 1);
+  EXPECT_EQ(0, drp_test_context_->pref_service()->GetInteger(
+                   data_reduction_proxy::prefs::kLoFiLoadImagesPerSession));
+  EXPECT_FALSE(user_opt_out_.value());
+}
+
 TEST_F(PreviewsInfoBarDelegateUnitTest, InfobarTestClickLinkLoFi) {
   base::HistogramTester tester;
 
   ConfirmInfoBarDelegate* infobar = CreateInfoBar(
       PreviewsInfoBarDelegate::LOFI, true /* is_data_saver_user */);
 
   // Simulate clicking the infobar link.
   if (infobar->LinkClicked(WindowOpenDisposition::CURRENT_TAB))
     infobar_service()->infobar_at(0)->RemoveSelf();
   EXPECT_EQ(0U, infobar_service()->infobar_count());
@@ skipping 162 matching lines @@
   if (infobar->LinkClicked(WindowOpenDisposition::CURRENT_TAB))
     infobar_service()->infobar_at(0)->RemoveSelf();
   EXPECT_EQ(0U, infobar_service()->infobar_count());
 
   content::WebContentsTester::For(web_contents())->CommitPendingNavigation();
 
   EXPECT_EQ(content::ReloadType::DISABLE_LOFI_MODE,
             TestPreviewsWebContentsObserver::FromWebContents(web_contents())
                 ->last_navigation_reload_type());
 }