NavigationURLLoaderImpl: Fix GCC build after #580595

Commit bf7722f9 ('Reland "Fixes
ExtensionWebRequestApiTest.WebRequestBlocking with network service"') caused
the GCC build to hit https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84849,
where having base::NoDestructor<T<U>> and passing an initializer list of Us
does not work.

Explicitly create an std::set<string> to pass to base::NoDestructor, just
like we did in https://chromium-review.googlesource.com/944405 before.

Bug: 819294
Change-Id: I8077b39959d8a53daef40bc33f8293f15c597ce0
Reviewed-on: https://chromium-review.googlesource.com/1165360Reviewed-by: Matt Menke <mmenke@chromium.org>
Reviewed-by: Charlie Harrison <csharrison@chromium.org>
Commit-Queue: Raphael Kubo da Costa (CET) <raphael.kubo.da.costa@intel.com>
Cr-Commit-Position: refs/heads/master@{#581287}

content/browser/loader/navigation_url_loader_impl.cc

@@ -313,10 +313,11 @@ bool IsURLHandledByDefaultLoader(const GURL& url) {
 
 // Determines whether it is safe to redirect to |url|.
 bool IsSafeRedirectTarget(const GURL& url, ResourceContext* resource_context) {
-  static base::NoDestructor<std::set<std::string>> kUnsafeSchemes({
-      url::kAboutScheme, url::kDataScheme, url::kFileScheme,
-      url::kFileSystemScheme,
-  });
+  static base::NoDestructor<std::set<std::string>> kUnsafeSchemes(
+      std::set<std::string>({
+          url::kAboutScheme, url::kDataScheme, url::kFileScheme,
+          url::kFileSystemScheme,
+      }));
   return !HasWebUIScheme(url) &&
          kUnsafeSchemes->find(url.scheme()) == kUnsafeSchemes->end() &&
          GetContentClient()->browser()->IsSafeRedirectTarget(url,