Decompose //extensions/browser/BUILD.gn

extensions/browser/guest_view/web_view/web_ui/BUILD.gn

Index: extensions/browser/guest_view/web_view/web_ui/BUILD.gn
diff --git a/services/file/public/cpp/BUILD.gn b/extensions/browser/guest_view/web_view/web_ui/BUILD.gn
similarity index 69%
copy from services/file/public/cpp/BUILD.gn
copy to extensions/browser/guest_view/web_view/web_ui/BUILD.gn
index f341a18b19af81ef3555e0516a57d41519a3b99b..9b26c4180764edd2ed8aa89af4af54f0e02b71b2 100644
--- a/services/file/public/cpp/BUILD.gn
+++ b/extensions/browser/guest_view/web_view/web_ui/BUILD.gn
@@ -2,9 +2,9 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("cpp") {
+source_set("web_ui") {
   sources = [
-    "constants.cc",
-    "constants.h",
+    "web_ui_url_fetcher.cc",
+    "web_ui_url_fetcher.h",
   ]
 }