WebAppMigrationUserDisplayModeCleanUpBrowserTest cleanup

DesktopPWAsWithoutExtensions has shipped.

The flag no longer needs to be enabled by tests.

Bug: 1065748
Change-Id: Ia9889f875fd5680ac56da38cec3e1ebcb46db715
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2459448
Auto-Submit: Eric Willigers <ericwilligers@chromium.org>
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Reviewed-by: Alan Cutter <alancutter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#815029}

chrome/browser/web_applications/web_app_migration_user_display_mode_clean_up_browsertest.cc

@@ -46,12 +46,8 @@ class WebAppMigrationUserDisplayModeCleanUpBrowserTest
     : public InProcessBrowserTest {
  public:
   WebAppMigrationUserDisplayModeCleanUpBrowserTest() {
-    scoped_feature_list_.InitWithFeatures(
-        {
-            features::kDesktopPWAsWithoutExtensions,
-            features::kDesktopPWAsMigrationUserDisplayModeCleanUp,
-        },
-        {});
+    scoped_feature_list_.InitAndEnableFeature(
+        features::kDesktopPWAsMigrationUserDisplayModeCleanUp);
     switch (GetTestPreCount()) {
       case 2:
         WebAppMigrationUserDisplayModeCleanUp::DisableForTesting();