Auto merge of #20750 - kwonoj:fix-wr-path, r=paulrouget

fix(capture_webrender): try fallback capture dir

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This PR try to update behavior of webrender capture to have fallback dir - first it try to create under current working dir, if fails go back to $TMPDIR. I was debating between TMP vs $home, bit hesitate to create some folder under user's home dir directly so choose TMP instead. Can be easily changed, or add few more if needed.

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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 #20746 (github issue number if applicable).

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- [ ] These changes do not require tests because _____
- locally verified on mac os

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components/compositing/compositor.rs

@@ -1404,17 +1404,24 @@ impl<Window: WindowMethods> IOCompositor<Window> {
     }
 
     pub fn capture_webrender(&mut self) {
-        match env::current_dir() {
-            Ok(current_dir) => {
-                let capture_id = now().to_timespec().sec.to_string();
-                let capture_path = current_dir.join("capture_webrender").join(capture_id);
+        let capture_id = now().to_timespec().sec.to_string();
+        let available_path = [env::current_dir(), Ok(env::temp_dir())].iter()
+            .filter_map(|val| val.as_ref().map(|dir| dir.join("capture_webrender").join(&capture_id)).ok())
+            .find(|val| {
+                match create_dir_all(&val) {
+                    Ok(_) => true,
+                    Err(err) => {
+                        eprintln!("Unable to create path '{:?}' for capture: {:?}", &val, err);
+                        false
+                    }
+                }
+            });
+
+        match available_path {
+            Some(capture_path) => {
                 let revision_file_path = capture_path.join("wr.txt");
 
-                if let Err(err) = create_dir_all(&capture_path) {
-                    eprintln!("Unable to create path '{:?}' for capture: {:?}", capture_path, err);
-                    return
-                }
-
+                debug!("Trying to save webrender capture under {:?}", &revision_file_path);
                 self.webrender_api.save_capture(capture_path, webrender_api::CaptureBits::all());
 
                 match File::create(revision_file_path) {
@@ -1427,7 +1434,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                     Err(err) => eprintln!("Capture triggered, creating webrender revision info skipped: {:?}", err)
                 }
             },
-            Err(err) => eprintln!("Unable to locate path to save captures: {:?}", err)
+            None => eprintln!("Unable to locate path to save captures")
         }
     }
 }