Upstream "nsurl_util.{h,mm}" from Chrome on iOS repository.

net/BUILD.gn

Index: net/BUILD.gn
diff --git a/net/BUILD.gn b/net/BUILD.gn
index 1815ea59b76208b9433aaa725d15ed05895a828a..f59f61a6e8c0ed53a57adcab6fc23c4c64d4b1db 100644
--- a/net/BUILD.gn
+++ b/net/BUILD.gn
@@ -498,6 +498,10 @@ component("net") {
     ]
   }
 
+  if (is_ios || is_mac) {
+    sources += gypi_values.net_base_mac_ios_sources
+  }
+
   if (is_android) {
     # Add some Linux sources that were excluded by the filter, but which
     # are needed.
@@ -1132,6 +1136,10 @@ test("net_unittests") {
     ]
   }
 
+  if (is_mac || is_ios) {
+    sources += gypi_values.net_base_test_mac_ios_sources
+  }
+
   if (is_chromeos) {
     sources -= [
       "proxy/proxy_config_service_linux_unittest.cc",