Allow generation of a chromium outdirs when enable_extensions=false

extensions/browser/api/app_current_window_internal/BUILD.gn

Index: extensions/browser/api/app_current_window_internal/BUILD.gn
diff --git a/extensions/browser/api/app_current_window_internal/BUILD.gn b/extensions/browser/api/app_current_window_internal/BUILD.gn
index 4877630508c514f9e8fe8bdf4eb69b26b2a702b2..32e292f555121b0490746950a4d5c678c4ee9384 100644
--- a/extensions/browser/api/app_current_window_internal/BUILD.gn
+++ b/extensions/browser/api/app_current_window_internal/BUILD.gn
@@ -2,6 +2,11 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//extensions/features/features.gni")
+
+assert(enable_extensions,
+       "Cannot depend on extensions because enable_extensions=false.")
+
 source_set("app_current_window_internal") {
   sources = [
     "app_current_window_internal_api.cc",