Enable feature RemoveStatusBarInWebApps by default on Chrome OS.

This change removes the status bar in installed WebApp windows (the
small text box that appears in the lower left hand corner of the
window).

Bug: 1151487
Change-Id: Ic1088730b7d6cdd622aedcefd1902e21741d7821
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2617479
Commit-Queue: Matt Giuca <mgiuca@chromium.org>
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Reviewed-by: Alan Cutter <alancutter@chromium.org>
Auto-Submit: Matt Giuca <mgiuca@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841404}

chrome/common/chrome_features.cc

@@ -735,7 +735,13 @@ const base::Feature kAbusiveNotificationPermissionRevocation{
     base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kRemoveStatusBarInWebApps{
-    "RemoveStatusBarInWebApps", base::FEATURE_DISABLED_BY_DEFAULT};
+    "RemoveStatusBarInWebApps",
+#if BUILDFLAG(IS_CHROMEOS_ASH) || BUILDFLAG(IS_CHROMEOS_LACROS)
+      base::FEATURE_ENABLED_BY_DEFAULT
+#else
+      base::FEATURE_DISABLED_BY_DEFAULT
+#endif
+};
 
 #if BUILDFLAG(IS_CHROMEOS_ASH)
 // Enables permanent removal of Legacy Supervised Users on startup.