Auto merge of #14284 - nox:fnv, r=Wafflespeanut

Use FnvHasher in http_loader::load

Should help with #11100.

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components/net/Cargo.toml

@@ -16,6 +16,7 @@ content-blocker = "0.2.1"
 cookie = {version = "0.2.5", features = ["serialize-rustc"]}
 devtools_traits = {path = "../devtools_traits"}
 flate2 = "0.2.0"
+fnv = "1.0"
 hyper = "0.9.9"
 hyper_serde = "0.1.4"
 immeta = "0.3.1"

components/net/http_loader.rs

@@ -11,6 +11,7 @@ use cookie_storage::CookieStorage;
 use devtools_traits::{ChromeToDevtoolsControlMsg, DevtoolsControlMsg, HttpRequest as DevtoolsHttpRequest};
 use devtools_traits::{HttpResponse as DevtoolsHttpResponse, NetworkEvent};
 use flate2::read::{DeflateDecoder, GzDecoder};
+use fnv::FnvHashSet;
 use hsts::{HstsEntry, HstsList, secure_url};
 use hyper::Error as HttpError;
 use hyper::LanguageTag;
@@ -42,7 +43,6 @@ use resource_thread::{AuthCache, AuthCacheEntry, CancellationListener, send_erro
 use servo_url::ServoUrl;
 use std::borrow::{Cow, ToOwned};
 use std::boxed::FnBox;
-use std::collections::HashSet;
 use std::error::Error;
 use std::fmt;
 use std::io::{self, Cursor, Read, Write};
@@ -898,7 +898,7 @@ pub fn load<A, B>(load_data: &LoadData,
     let mut iters = 0;
     // URL of the document being loaded, as seen by all the higher-level code.
     let mut doc_url = load_data.url.clone();
-    let mut redirected_to = HashSet::new();
+    let mut redirected_to = FnvHashSet::with_hasher(Default::default());
     let mut method = load_data.method.clone();
     // URL of referrer - to be updated with redirects
     let mut referrer_url = load_data.referrer_url.clone();

components/net/lib.rs

@@ -18,6 +18,7 @@ extern crate content_blocker as content_blocker_parser;
 extern crate cookie as cookie_rs;
 extern crate devtools_traits;
 extern crate flate2;
+extern crate fnv;
 extern crate hyper;
 extern crate hyper_serde;
 extern crate immeta;