Move CSP code into one entrypoint (#37604)

This refactoring moves various CSP-related methods away from GlobalScope
and Document into a dedicated entrypoint. It also reduces the amount of
imports of the CSP crate, so that types are consolidated into this one
entrypoint. That way, we control how CSP code interacts with the script
crate.

For reviewing purposes, I split up the refactoring into separate
distinct commits that all move 1 method(group) into the new file.

Testing: no change in behavior, only a build improvement + code cleanup

---------

Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com>
Signed-off-by: Tim van der Lippe <TimvdLippe@users.noreply.github.com>

components/script/stylesheet_loader.rs

@@ -5,7 +5,6 @@
 use std::io::{Read, Seek, Write};
 use std::sync::atomic::AtomicBool;
 
-use content_security_policy as csp;
 use cssparser::SourceLocation;
 use encoding_rs::UTF_8;
 use mime::{self, Mime};
@@ -32,6 +31,7 @@ use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::refcounted::Trusted;
 use crate::dom::bindings::reflector::DomGlobal;
 use crate::dom::bindings::root::DomRoot;
+use crate::dom::csp::{GlobalCspReporting, Violation};
 use crate::dom::document::Document;
 use crate::dom::element::Element;
 use crate::dom::eventtarget::EventTarget;
@@ -296,7 +296,7 @@ impl FetchResponseListener for StylesheetContext {
         network_listener::submit_timing(self, CanGc::note())
     }
 
-    fn process_csp_violations(&mut self, _request_id: RequestId, violations: Vec<csp::Violation>) {
+    fn process_csp_violations(&mut self, _request_id: RequestId, violations: Vec<Violation>) {
         let global = &self.resource_timing_global();
         global.report_csp_violations(violations, None);
     }