Clean up download_prefs code using legacy drive sync client

DriveFS is going to be used regardless of its feature flag, and the
legacy drive sync client will be deleted, so clean up code that relies
on the legacy drive sync client.

Bug: 1002339
Change-Id: I85827f39bd174362a9a9e37eb5721384fea37d69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1798947Reviewed-by: Min Qin <qinmin@chromium.org>
Commit-Queue: Austin Tankiang <austinct@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697056}

chrome/browser/download/download_prefs_unittest.cc

@@ -13,11 +13,9 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "base/test/scoped_feature_list.h"
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/login/users/fake_chrome_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
-#include "chromeos/constants/chromeos_features.h"
 #include "components/drive/drive_pref_names.h"
 #include "content/public/test/test_service_manager_context.h"
 #endif
@@ -221,32 +219,8 @@ TEST(DownloadPrefsTest, DownloadDirSanitization) {
                                 parent_reference.value());
   EXPECT_EQ(prefs.DownloadPath(), default_dir);
 
-  // Drive
-  {
-    base::test::ScopedFeatureList features;
-    features.InitAndDisableFeature(chromeos::features::kDriveFs);
-    auto* integration_service =
-        drive::DriveIntegrationServiceFactory::GetForProfile(&profile);
-    integration_service->SetEnabled(true);
-
-    // My Drive root.
-    ExpectValidDownloadDir(
-        &profile, &prefs,
-        base::FilePath("/special/drive-0123456789abcdef/root"));
-    // My Drive/foo.
-    ExpectValidDownloadDir(
-        &profile, &prefs,
-        base::FilePath("/special/drive-0123456789abcdef/root/foo"));
-    // Invalid path without one of the drive roots.
-    profile.GetPrefs()->SetString(prefs::kDownloadDefaultDirectory,
-                                  "/special/drive-0123456789abcdef");
-    EXPECT_EQ(prefs.DownloadPath(), default_dir);
-  }
-
   // DriveFS
   {
-    base::test::ScopedFeatureList features;
-    features.InitAndEnableFeature(chromeos::features::kDriveFs);
     // Create new profile for enabled feature to work.
     TestingProfile profile2(base::FilePath("/home/chronos/u-0123456789abcdef"));
     chromeos::FakeChromeUserManager user_manager;