Make NSS work in GN build on Windows.

build/config/BUILDCONFIG.gn

Index: build/config/BUILDCONFIG.gn
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index 18d1140a1345dde53adc8664eddaf10f23bab65c..280fccd93a5a3df86c52dd5003ca24e1bc225648 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -347,7 +347,11 @@ native_compiler_configs = [
   "//build/config/compiler:runtime_library",
 ]
 if (is_win) {
-  native_compiler_configs += [ "//build/config/win:sdk", ]
+  native_compiler_configs += [
+    "//build/config/win:lean_and_mean",
+    "//build/config/win:sdk",
+    "//build/config/win:unicode",
+  ]
 } else if (is_linux) {
   native_compiler_configs += [ "//build/config/linux:sdk", ]
 } else if (is_mac) {
@@ -357,6 +361,9 @@ if (is_win) {
 } else if (is_android) {
   native_compiler_configs += [ "//build/config/android:sdk", ]
 }
+if (!is_win) {
+  native_compiler_configs += [ "//build/config/gcc:symbol_visibility_hidden" ]
+}
 if (is_clang) {
   native_compiler_configs += [ "//build/config/clang:find_bad_constructs" ]
 }