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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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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tests/unit/style/Cargo.toml

@@ -13,6 +13,7 @@ doctest = false
 byteorder = "1.0"
 app_units = "0.6"
 cssparser = "0.23.0"
+embedder_traits = {path = "../../../components/embedder_traits"}
 euclid = "0.17"
 html5ever = "0.22"
 parking_lot = "0.5"

tests/unit/style/lib.rs

@@ -7,6 +7,7 @@
 
 extern crate app_units;
 extern crate cssparser;
+extern crate embedder_traits;
 extern crate euclid;
 #[macro_use] extern crate html5ever;
 extern crate parking_lot;

tests/unit/style/stylesheets.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use cssparser::{self, SourceLocation};
+use embedder_traits::resources::register_resources_for_tests;
 use html5ever::{Namespace as NsAtom};
 use media_queries::CSSErrorReporterTest;
 use parking_lot::RwLock;
@@ -321,6 +322,7 @@ impl ParseErrorReporter for TestingErrorReporter {
 
 #[test]
 fn test_report_error_stylesheet() {
+    register_resources_for_tests();
     PREFS.set("layout.viewport.enabled", PrefValue::Boolean(true));
     let css = r"
     div {