Auto merge of #12463 - asajeffrey:url-errors-should-be-warnings, r=Ms2ger

Replace any errors caused by content-provided URLs by warnings.

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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 do not require tests because we don't test error generation

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components/compositing/compositor.rs

@@ -1403,7 +1403,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                     warn!("Sending load url to constellation failed ({}).", e);
                 }
             },
-            Err(e) => error!("Parsing URL {} failed ({}).", url_string, e),
+            Err(e) => warn!("Parsing URL {} failed ({}).", url_string, e),
         }
     }
 

components/script/dom/htmlscriptelement.rs

@@ -328,7 +328,7 @@ impl HTMLScriptElement {
                 // Step 18.4-18.5.
                 let url = match base_url.join(&src) {
                     Err(_) => {
-                        error!("error parsing URL for script {}", &**src);
+                        warn!("error parsing URL for script {}", &**src);
                         self.queue_error_event();
                         return NextParserState::Continue;
                     }
@@ -414,7 +414,7 @@ impl HTMLScriptElement {
         let (source, external, url) = match load {
             // Step 2.a.
             ScriptOrigin::External(Err(e)) => {
-                error!("error loading script {:?}", e);
+                warn!("error loading script {:?}", e);
                 self.dispatch_error_event();
                 return;
             }