Revert "User data downgrade: Test snapshot tabs state"

This reverts commit dfd901d6.

Reason for revert: TabsSnapshotTest.Test is > 50% flakey.

See https://ci.chromium.org/p/chromium/builders/ci/linux-trusty-rel/8642

Original change's description:
> User data downgrade: Test snapshot tabs state
> 
> Bug: 958893
> Change-Id: If0cc3e0cd1e70a3b21c675b3979166f7aaba554d
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2076438
> Commit-Queue: Yann Dago <ydago@chromium.org>
> Reviewed-by: Greg Thompson <grt@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#745474}

TBR=grt@chromium.org,ydago@chromium.org

Change-Id: Idab515fc68a966222463a74341f46929464d97c8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 958893
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2080811Reviewed-by: Chris Mumford <cmumford@google.com>
Commit-Queue: Chris Mumford <cmumford@google.com>
Cr-Commit-Position: refs/heads/master@{#745609}

chrome/browser/downgrade/user_data_snapshot_browsertest.cc

@@ -24,25 +24,18 @@
 #include "chrome/browser/history/history_service_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
-#include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_result_codes.h"
 #include "chrome/common/chrome_switches.h"
-#include "chrome/common/pref_names.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "components/bookmarks/browser/bookmark_model.h"
 #include "components/bookmarks/browser/bookmark_node.h"
 #include "components/history/core/browser/history_service.h"
 #include "components/history/core/browser/history_types.h"
 #include "components/keyed_service/core/service_access_type.h"
-#include "components/prefs/pref_service.h"
 #include "components/version_info/version_info.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/common/referrer.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
-#include "ui/base/page_transition_types.h"
-#include "ui/base/window_open_disposition.h"
 
 namespace downgrade {
 
@@ -370,45 +363,4 @@ IN_PROC_BROWSER_TEST_F(HistorySnapshotTest, PRE_PRE_Test) {}
 IN_PROC_BROWSER_TEST_F(HistorySnapshotTest, PRE_Test) {}
 IN_PROC_BROWSER_TEST_F(HistorySnapshotTest, Test) {}
 
-class TabsSnapshotTest : public UserDataSnapshotBrowserTestBase {
- protected:
-  void SetUp() override {
-    ASSERT_TRUE(embedded_test_server()->Start());
-    set_open_about_blank_on_browser_launch(IsInitialVersion());
-    UserDataSnapshotBrowserTestBase::SetUp();
-  }
-
-  void SimulateUserActions() override {
-    browser()->profile()->GetPrefs()->SetInteger(prefs::kRestoreOnStartup, 1);
-    browser()->tab_strip_model()->GetWebContentsAt(0)->OpenURL(
-        content::OpenURLParams(embedded_test_server()->GetURL("/title1.html"),
-                               content::Referrer(),
-                               WindowOpenDisposition::CURRENT_TAB,
-                               ui::PAGE_TRANSITION_TYPED, false));
-    browser()->tab_strip_model()->GetWebContentsAt(0)->OpenURL(
-        content::OpenURLParams(embedded_test_server()->GetURL("/title2.html"),
-                               content::Referrer(),
-                               WindowOpenDisposition::NEW_FOREGROUND_TAB,
-                               ui::PAGE_TRANSITION_TYPED, false));
-  }
-
-  void ValidateUserActions() override {
-    EXPECT_EQ(
-        browser()->profile()->GetPrefs()->GetInteger(prefs::kRestoreOnStartup),
-        1);
-    auto* tab_strip = browser()->tab_strip_model();
-    ASSERT_EQ(tab_strip->count(), 2);
-    // embedded_test_server() might return a different hostname.
-    EXPECT_TRUE(base::EndsWith(tab_strip->GetWebContentsAt(0)->GetURL().spec(),
-                               "/title1.html", base::CompareCase::SENSITIVE));
-    EXPECT_TRUE(base::EndsWith(tab_strip->GetWebContentsAt(1)->GetURL().spec(),
-                               "/title2.html", base::CompareCase::SENSITIVE));
-  }
-};
-
-IN_PROC_BROWSER_TEST_F(TabsSnapshotTest, PRE_PRE_PRE_Test) {}
-IN_PROC_BROWSER_TEST_F(TabsSnapshotTest, PRE_PRE_Test) {}
-IN_PROC_BROWSER_TEST_F(TabsSnapshotTest, PRE_Test) {}
-IN_PROC_BROWSER_TEST_F(TabsSnapshotTest, Test) {}
-
 }  // namespace downgrade