Auto merge of #14736 - deror1869107:Move-reg_host-to-pub_domains, r=Ms2ger

Move reg_host from the constellation to net_traits

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Move reg_host from the constellation to net_traits

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #14696  (github issue number if applicable).

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- [X] These changes do not require tests

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components/constellation/constellation.rs

@@ -86,7 +86,7 @@ use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use msg::constellation_msg::{PipelineNamespace, PipelineNamespaceId, TraversalDirection};
 use net_traits::{self, IpcSend, ResourceThreads};
 use net_traits::image_cache_thread::ImageCacheThread;
-use net_traits::pub_domains::reg_suffix;
+use net_traits::pub_domains::reg_host;
 use net_traits::storage_thread::{StorageThreadMsg, StorageType};
 use offscreen_gl_context::{GLContextAttributes, GLLimits};
 use pipeline::{InitialPipelineState, Pipeline};
@@ -644,14 +644,6 @@ fn log_entry(record: &LogRecord) -> Option<LogEntry> {
 /// The number of warnings to include in each crash report.
 const WARNINGS_BUFFER_SIZE: usize = 32;
 
-/// The registered domain name (aka eTLD+1) for a URL.
-/// Returns None if the URL has no host name.
-/// Returns the registered suffix for the host name if it is a domain.
-/// Leaves the host name alone if it is an IP address.
-fn reg_host<'a>(url: &'a ServoUrl) -> Option<&'a str> {
-    url.domain().map(reg_suffix).or(url.host_str())
-}
-
 impl<Message, LTF, STF> Constellation<Message, LTF, STF>
     where LTF: LayoutThreadFactory<Message=Message>,
           STF: ScriptThreadFactory<Message=Message>

components/net_traits/pub_domains.rs

@@ -15,6 +15,7 @@
 //! those cases are not present.
 
 use servo_config::resource_files::read_resource_file;
+use servo_url::ServoUrl;
 use std::collections::HashSet;
 use std::iter::FromIterator;
 use std::str::from_utf8;
@@ -138,3 +139,11 @@ pub fn is_pub_domain(domain: &str) -> bool {
 pub fn is_reg_domain(domain: &str) -> bool {
     PUB_DOMAINS.is_registrable_suffix(domain)
 }
+
+/// The registered domain name (aka eTLD+1) for a URL.
+/// Returns None if the URL has no host name.
+/// Returns the registered suffix for the host name if it is a domain.
+/// Leaves the host name alone if it is an IP address.
+pub fn reg_host<'a>(url: &'a ServoUrl) -> Option<&'a str> {
+    url.domain().map(reg_suffix).or(url.host_str())
+}