Auto merge of #20533 - paulrouget:res, r=mbrubeck

Delegate resource reading to embedder

Now the embedder provides the content of the files itself. Now, on Android, we can use regular assets instead of unzipping all the resources on the scared at startup.

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- [ ] `./mach build-geckolib` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #15635 (github issue number if applicable).

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- [ ] These changes do not require tests because _____

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components/script/dom/servoparser/mod.rs

@@ -30,6 +30,7 @@ use dom::processinginstruction::ProcessingInstruction;
 use dom::text::Text;
 use dom::virtualmethods::vtable_for;
 use dom_struct::dom_struct;
+use embedder_traits::resources::{self, Resource};
 use html5ever::{Attribute, ExpandedName, LocalName, QualName};
 use html5ever::buffer_queue::BufferQueue;
 use html5ever::tendril::{StrTendril, ByteTendril, IncompleteUtf8};
@@ -45,7 +46,6 @@ use profile_traits::time::{TimerMetadataReflowType, ProfilerCategory, profile};
 use script_thread::ScriptThread;
 use script_traits::DocumentActivity;
 use servo_config::prefs::PREFS;
-use servo_config::resource_files::read_resource_file;
 use servo_url::ServoUrl;
 use std::borrow::Cow;
 use std::cell::Cell;
@@ -671,16 +671,14 @@ impl FetchResponseListener for ParserContext {
                 // Handle text/html
                 if let Some(reason) = ssl_error {
                     self.is_synthesized_document = true;
-                    let page_bytes = read_resource_file("badcert.html").unwrap();
-                    let page = String::from_utf8(page_bytes).unwrap();
+                    let page = resources::read_string(Resource::BadCertHTML);
                     let page = page.replace("${reason}", &reason);
                     parser.push_string_input_chunk(page);
                     parser.parse_sync();
                 }
                 if let Some(reason) = network_error {
                     self.is_synthesized_document = true;
-                    let page_bytes = read_resource_file("neterror.html").unwrap();
-                    let page = String::from_utf8(page_bytes).unwrap();
+                    let page = resources::read_string(Resource::NetErrorHTML);
                     let page = page.replace("${reason}", &reason);
                     parser.push_string_input_chunk(page);
                     parser.parse_sync();

components/script/dom/userscripts.rs

@@ -8,7 +8,6 @@ use dom::htmlheadelement::HTMLHeadElement;
 use dom::node::Node;
 use js::jsval::UndefinedValue;
 use servo_config::opts;
-use servo_config::resource_files::resources_dir_path;
 use std::fs::{File, read_dir};
 use std::io::Read;
 use std::path::PathBuf;
@@ -22,17 +21,7 @@ pub fn load_script(head: &HTMLHeadElement) {
         let cx = win.get_cx();
         rooted!(in(cx) let mut rval = UndefinedValue());
 
-        let path = if &**path_str == "" {
-            if let Ok(mut p) = resources_dir_path() {
-                p.push("user-agent-js");
-                p
-            } else {
-                return
-            }
-        } else {
-            PathBuf::from(path_str)
-        };
-
+        let path = PathBuf::from(path_str);
         let mut files = read_dir(&path).expect("Bad path passed to --userscripts")
                                        .filter_map(|e| e.ok())
                                        .map(|e| e.path()).collect::<Vec<_>>();