Auto merge of #11727 - creativcoder:swmanager, r=jdm

Integrate service worker manager thread

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---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes are part of #11091

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- [X] There are tests for these changes at my [gh-pages](https://github.com/creativcoder/gsoc16/tree/gh-pages) branch to test  the instantiation of service workers by their manager, but will need to discuss how that would integrate into master.

Changes:
- Introduces a `ServiceWorkerManager`, which maintains an map of registered service workers as well as a map of active workers keyed by their `scope_url`.
- Adds the initialization of ServiceWorkerManager, at the `script::init()`, which makes it available as a single entity listening for requests from different script threads.
- Adds a timeout thread in `serviceworkerglobalscope`, which terminates the workers, after a timeout of 60 secs, thereby removing it from the active workers list.
- Adds the matching of scope urls, in longest prefix way rather than path structural way, according to [spec](https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#scope-match-algorithm).
- Make ServiceWorkerManager, the holder of network sender, instead of script thread, so it can send `CustomResponse`.

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1 files changed, 1 insertions, 8 deletions

diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index ed254f8c007..9ac02936673 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -47,7 +47,7 @@ use net_traits::CoreResourceMsg::Fetch;
 use net_traits::request::{CredentialsMode, Destination, RequestInit, RequestMode};
 use net_traits::trim_http_whitespace;
 use net_traits::{CoreResourceThread, LoadOrigin};
-use net_traits::{FetchResponseListener, Metadata, NetworkError, RequestSource};
+use net_traits::{FetchResponseListener, Metadata, NetworkError};
 use network_listener::{NetworkListener, PreInvoke};
 use parse::html::{ParseContext, parse_html};
 use parse::xml::{self, parse_xml};
@@ -274,13 +274,6 @@ impl LoadOrigin for XMLHttpRequest {
     fn referrer_policy(&self) -> Option<ReferrerPolicy> {
         return self.referrer_policy;
     }
-    fn request_source(&self) -> RequestSource {
-        if self.sync.get() {
-            RequestSource::None
-        } else {
-            self.global().r().request_source()
-        }
-    }
     fn pipeline_id(&self) -> Option<PipelineId> {
         let global = self.global();
         Some(global.r().pipeline())