Advertise brotli for localhost requests.

net/url_request/url_request_http_job.cc

Index: net/url_request/url_request_http_job.cc
diff --git a/net/url_request/url_request_http_job.cc b/net/url_request/url_request_http_job.cc
index 7855fe25cac0af1be6f9e46ac04752f4c1274ae7..a398986da32fc39d59e47055b80fc5888f49b33a 100644
--- a/net/url_request/url_request_http_job.cc
+++ b/net/url_request/url_request_http_job.cc
@@ -716,8 +716,12 @@ void URLRequestHttpJob::AddExtraHeaders() {
 
     // Advertise "br" encoding only if transferred data is opaque to proxy.
     bool advertise_brotli = false;
-    if (request()->context()->enable_brotli())
-      advertise_brotli = request()->url().SchemeIsCryptographic();
+    if (request()->context()->enable_brotli()) {
+      if (request()->url().SchemeIsCryptographic() ||
+          IsLocalhost(request()->url().HostNoBrackets())) {
+        advertise_brotli = true;
+      }
+    }
 
     // Supply Accept-Encoding headers first so that it is more likely that they
     // will be in the first transmitted packet. This can sometimes make it