diff -up chromium-76.0.3809.132/services/network/cross_origin_read_blocking.cc.gcc-ambigous-instantiation chromium-76.0.3809.132/services/network/cross_origin_read_blocking.cc
--- chromium-76.0.3809.132/services/network/cross_origin_read_blocking.cc.gcc-ambigous-instantiation	2019-08-26 21:02:33.000000000 +0200
+++ chromium-76.0.3809.132/services/network/cross_origin_read_blocking.cc	2019-08-27 06:58:23.963821667 +0200
@@ -207,7 +207,7 @@ std::set<int>& GetPluginProxyingProcesse
 // confirmation sniffing because images, scripts, etc. are frequently
 // mislabelled by http servers as HTML/JSON/XML).
 base::flat_set<std::string>& GetNeverSniffedMimeTypes() {
-  static base::NoDestructor<base::flat_set<std::string>> s_types({
+  static base::NoDestructor<base::flat_set<std::string>> s_types{{
       // The list below has been populated based on most commonly used content
       // types according to HTTP Archive - see:
       // https://github.com/whatwg/fetch/issues/860#issuecomment-457330454
@@ -219,7 +219,7 @@ base::flat_set<std::string>& GetNeverSni
       "application/x-protobuf",
       "application/zip",
       "text/event-stream",
-  });
+  }};
 
   // All items need to be lower-case, to support case-insensitive comparisons
   // later.